Trace but...

His most dangerous reaction
She might get nervous and draw attention to herself: her attempts to act normally could be so clumsy that they arouse suspicion.
She would be afraid of being involved in something serious: she might worry about the consequences of keeping your secret.
He would probably try to understand you: if you explain that you are scared and don't want to hurt anyone, he might empathize.
She could turn to someone she trusts: if she feels unable to handle the situation, she might seek guidance instead of trying to investigate you on her own.
—“I-I… I don’t want to get you into trouble… B-but I don’t know what I should do either!”
If you ask him to be quiet, he might nod nervously.
—“Y-yes! I won’t say anything! B-but… promise me you won’t hurt anyone!”
Would she be dangerous? Not so much because of her ability to deliberately expose you, but because her nerves could make the situation worse. She might also end up asking for help if she feels the situation is beyond her control.

His most dangerous reaction
I would ask you endless questions: how you got here, why you disguised yourself, and how you managed to deceive the others.
He would try to approach you: his friendly nature might make him want to get to know you better instead of rejecting you.
She could unintentionally reveal the secret: if she gets too excited, she risks mentioning it out loud in front of other students.
I would like to help you if I see you're scared: once I understand that the situation is serious, I might try to control my enthusiasm and support you.
—"Okay, okay! I won't say anything! Your secret is safe with me!"
Five minutes later, when a friend appears:
—“Hey! You won’t believe what I just discovered about…!”
—"TAIKI, NO!".
Would she be dangerous? More because of her lack of discretion in moments of excitement than because of any intention to trap you. If you can explain to her how important it is to keep quiet, she could become quite a cheerful ally.

When you confess, she doesn't seem surprised for very long.
—"I understand. So, you're human."
What would I do next?
I would ask you about your motives and the method you used to gain entry.
I'd like to know if anyone else knows your secret.
I would assess whether your presence could endanger other students.
He wouldn't be convinced by just a sad story: he would need reasons to trust you.
If he concludes that you are not a threat, he might agree to listen to you and allow you to explain your situation before judging you.
Duramente didn't have to be cruel to be intimidating. His determination and his direct approach to the problem would be enough.
—“I’m not going to decide who you are solely based on your human nature. But I’m also not going to ignore what you’ve done.”
Would I help you? It might be possible if you demonstrate honesty and responsibility. However, I would probably be among the least willing to participate in an indefinite cover-up.

The funniest thing would be that your attempt to keep the secret would end up becoming, in his mind, a matter of honor.
What would I do next?
I would demand a sincere explanation from you.
I would try to determine if your intentions are noble or selfish.
He could offer to accompany you while you look for a solution.
If you believe you are putting other students at risk, I would insist that you take responsibility for your actions.
Durandal might interpret your infiltration as a test of character: not so much whether you are human or Umamusume, but whether you are capable of admitting the truth and accepting the consequences.
—“Courage is not about hiding your identity forever! It’s about facing the truth when the time comes!”
Would she help you? Yes, if she believes you're trying to do the right thing. But it wouldn't be easy to convince her that continuing to deceive the entire academy is an honorable solution.

When you finally confess that you are human, she is surprised.
—“A human?! Wait… Does that mean you’ve been taking risks all this time?”
What would I do next?
He would worry about your safety and what might happen to you if you were discovered.
I would ask if someone forced you to do it or if you made the decision on your own.
I would try to help you think clearly, especially if you're panicking.
If he understands that you have committed a serious infraction, he would also insist that you have to face the situation.
Their biggest conflict would be that they might want to protect you, but not know if they're doing the right thing by keeping your secret.
—"I really want to help you. But I can't promise that everything will be alright if we keep hiding it."
Would she help you? She'd probably be one of the best people to talk to without turning the conversation into a fight. However, she might end up seeking help from a responsible adult if she thinks your situation is becoming dangerous.

What would I do next?
I would confront you directly.
I'd like to know how you got into Tracen.
If she suspects you're taking advantage of a female colleague, she'll quickly lose patience.
If he discovers that you are scared and that you don't have bad intentions, he might moderate his attitude.
The curious thing is that, if she were to come to respect you, your humanity might cease to be the most important thing to her. Jungle Pocket highly values ​​competitive spirit and determination, so she might be interested to know why you dared to do something so risky.
—“I don’t care if you’re human or whatever you are! But stop hiding and tell me the truth!”
Would he help you? Yes, it's possible, but you'd have to earn his respect. Lying to him after he finds out would be a terrible idea.

Within the supernatural interpretation of her personality, she might associate your presence with that invisible figure she habitually perceives. This doesn't mean she can canonically detect human infiltrators; that would be an extrapolation for this scenario.
What would I do next?
I would discreetly observe you to confirm my suspicions.
She would ask you unexpected questions, especially if she notices you're nervous.
I would try to understand if you are hiding something dangerous or are simply afraid.
If he considers you harmless, he might remain silent for a while.
The most terrifying thing would be not knowing how much he has actually discovered.
—"You don't have to tell me now... But I don't think you're who you say you are."
Would she help you? Possibly, if she came to trust you. Café wouldn't necessarily be the first to report you, but she would certainly be one of those who would unsettle you the most without raising her voice.

First reaction: disbelief, excitement, and a fanatic meltdown.
Digital might discover you for a completely different reason: not by studying your body, but because they notice something odd about your disguise. Perhaps your ears seem too stiff, your tail moves unnaturally, or you make a mistake when talking about Umamusume.

She could accidentally expose you. Her enthusiasm might cause her to talk too loudly, follow you down the hallways, or almost reveal your identity in front of other students.
I'd like to know your opinion on Umamusume. And she might get especially nervous if you tell her you admire any of them.
The greatest danger with Digital would not be a calculated investigation, but rather that his emotion would overcome his common sense.
—“Relax! I won’t say a word! Your secret is safe with me!”
A few minutes later, upon seeing several students walk by:
—“Oh, how wonderful! I’m sharing an academy with a real human and nobody knows it!”
You slowly turn towards her.
—"Digital... you just said it out loud."
—“……AAAAAH! I’M SORRY!”
Could you trust her?
She would probably be the easiest to convince to help you out of affection and enthusiasm. However, you would need to explain clearly that keeping the secret is important: simply asking her not to tell anyone once wouldn't be enough.

First reaction: absolute scientific curiosity.
Imagine you're in a hallway, trying to avoid having your real ears and fake tail discovered. Tachyon watches you run a few meters and notices that your movement doesn't match that of an Umamusume.
At first I wouldn't accuse you. I would simply smile.
—“Hmm… That’s strange. Your posture, your breathing, and the distribution of your strength don’t match my observations. Could you explain that to me?”
You would try to make up an excuse, but she would already be thinking of ten other questions.
The most worrying thing would be that Tachyon wouldn't simply consider you an offender: it would see you as an extraordinary scientific discovery.
If you tried to escape from her, she probably wouldn't chase you immediately. First, she would try to predict where you would go, what you would do to hide, and what mistakes you would make.
—“Wait, wait! We’re not finished yet! We haven’t even gotten to the interesting part!”
Could you trust her?
To a certain extent. Tachyon might keep your secret if it allowed him to continue investigating you, but it wouldn't be wise to assume he would prioritize your privacy over his curiosity.

—Before deciding what should be done about you, I want to know exactly what happened and what information you have hidden.
He wouldn't be swayed solely by an emotional apology, but neither would he assume the infiltrator was dangerous. He would examine their actions, their motivations, and the available evidence.
If it is discovered that the human has been monitoring students or accessing restricted areas, the investigation would become much more serious.
If he discovers that she was only seeking to study and train alongside the Umamusume: he would still consider the deception a serious matter, but he would distinguish that situation from an infiltration intended to cause harm.
Note: I cannot confirm with sufficient certainty that Fenomeno officially holds the position of head of the public discipline department that you mention; that part is presented as a premise of your scenario.

But her sense of justice would also be important: she shouldn't condemn him simply for being human. If she discovered that he hadn't stolen, assaulted, or harmed anyone, she would distinguish between identity theft and other unproven crimes.
If the human tries to flee: Bamboo Memory would immediately pursue them and demand that they stop.
If the human surrenders voluntarily: I would still be strict, but I would be more willing to listen to their statement and recognize that cooperating is better than aggravating the situation.

Her own story is marked by perseverance and recovery from physical hardship. Therefore, she could understand someone's desire to overcome their limitations, though not necessarily the decision to do so through a false identity.
If the human had participated in races, he would insist that his results not be used to draw hasty conclusions about his abilities.
If he discovers that the infiltrator was injured and still continued training, he'll be furious. Not because he's human, but because he'd concealed a situation that could end up seriously harming him.
Note: This is a narrative interpretation of his personality; his specific inclusion in a Tracen medical department should not be taken as official without a concrete source.

Ardan would maintain her composure even if the revelation were completely unexpected. She wouldn't be one to start shouting or accuse the human in front of everyone; she would prefer to speak with him in private.
—I understand you had your reasons. However, hiding who you are for so long is not something to be taken lightly.
Due to his own relationship with physical frailty and the limitations of his body, he might be especially sensitive to the fact that a human had subjected himself to physical demands that were not necessarily appropriate for him.
He would be interested in finding out if the infiltrator had been aware of the risks and if he had received help to cope with them.
If he discovers that the human pushed himself to the point of exhaustion to avoid falling behind, his expression would become more sad than stern. He might respect their determination, but he would reproach them for confusing personal sacrifice with the need to conceal the truth.

Perhaps she would try to sit him down, offer him something to drink, and reassure him before asking any questions. Her affectionate way of treating him might confuse him even more, especially if he expected everyone to reject him.
However, her tenderness didn't mean she condoned the lie. If her life had been endangered, Super Creek would have been much more resolute.
If he discovers that the human infiltrated because he wanted to belong to Tracen: he would feel compassion for his loneliness, although he would insist that he doesn't need to risk his health to deserve someone's appreciation.

If she discovered that one of her students had impersonated an Umamusume, her reaction would depend on how long she had worked with him.
He would feel responsible for not having discovered the truth sooner. He would review his training, his records, and any injuries he might have suffered.
—You trusted me to train you, but you never told me who you really were. I need to know why.
If the human had earned his respect through dedication, he would try to distinguish talent and effort from falsification. However, he wouldn't allow him to compete without first verifying that doing so was safe and legal.

Riko would be especially strict if the infiltrator had competed under a false identity. Her disciplinary approach would lead her to examine the results, the training conditions, and any potential advantages or disadvantages gained through deception.
—You can't change the rules simply because you managed to deceive those who were supposed to enforce them.
It would probably require a thorough investigation and measures to prevent something like this from happening again.
However, if the human had demonstrated that they were capable of following a training program without putting others at risk, they could accept having their case evaluated individually, always within the applicable rules.

Hana would react with firmness and pragmatism. As a trainer, she would be concerned that the human had participated in activities not designed for their physiology.
—I want to know what you've been doing, how much you've trained, and if anyone has forced you to maintain this lie.
He wouldn't settle for just an excuse. He'd want to examine three issues: the deception, the physical risks, and the personal motivations.
If the human had worked hard to be on par with his female colleagues, he could respect his effort without condoning identity theft.

Aoi would react with a mixture of surprise and practical concern. She would want to know how the infiltrator managed to train among the Umamusume without anyone noticing any differences in his stamina, recovery, and physical abilities.
—Have you been following these training programs all this time? You could have hurt yourself!
If the human had participated in demanding exercises, his attention would have focused on assessing his physical condition and checking if the workouts were suitable for him.
Although he would be angry about the deception, he wouldn't want the discovery to end with the human injured or left to their fate.

Director Akikawa would be a key figure in resolving the incident. Her initial reaction might be disbelief, followed by a thorough investigation.
—A human infiltrated in our prestigious academy?! This requires an immediate investigation!
His forceful nature could make the situation seem even more dramatic. He would need to know the infiltrator's motives and determine if there were any failures in the admission procedures.
If the human had demonstrated extraordinary dedication and hadn't harmed anyone, the case could be pursued in an unconventional way. However, enthusiasm wouldn't replace the necessary checks.

Tazuna would be alarmed to discover that a human had managed to enter under a false identity. His first concern would be how they could have gone unnoticed for so long.
—Wait... are you telling me that all these records are in the name of someone who isn't even an Umamusume?
She would review the documentation, the registrations, and the access controls. If the infiltrator had been kind and respectful to her, she would try to listen to him before judging him, but she couldn't ignore the seriousness of the situation.
If the human had confessed voluntarily, he would probably be grateful that I hadn't waited for an accident to happen to reveal the truth.

Urara would probably take some time to understand all the implications.
—Huh? So you're not an Uma Musume? But... we're still friends, right?!
He would worry less about formalities at first and more about whether the friendship had been real.
If I discovered that the human never intended to cause harm, I could continue treating them kindly. That wouldn't prevent the academy officials from investigating the deception.

Rice Shower would feel scared and confused. If the human had been her friend, she might interpret the lie as a sign that he never truly trusted her.
—Rice... I thought we could be real friends.
However, I would be able to understand that someone might lie out of fear, desperation, or a desire to belong to a place from which they feel excluded.
If the human were to sincerely apologize, Rice could be one of the first to give him the opportunity to explain his feelings, although he would need to gradually regain her trust.

Oguri would probably be surprised and then ask an unexpectedly simple question.
—So... you can eat the same things as us?
Once he understood the seriousness of the matter, he would want to know if the human was alright and if he could really withstand the training.
She wouldn't necessarily be naive about the lie; she might simply focus first on what's in front of her. If she discovered that someone had forced her to infiltrate, her concern for the human would increase.

Air Groove would react severely, especially if there were indications that the human bypassed access controls or falsified records.
"I don't care how long you've managed to keep up the lie. You're going to explain every single infraction you've committed."
I would demand a thorough investigation, a review of the training sessions, and confirmation that no student was harmed. I would not tolerate Gold Ship turning the investigation into a circus.
If the infiltrator cooperated, Air Groove could acknowledge his belated sincerity, but would not mistake that sincerity for the absence of consequences.

Rudolf would be one of the hardest people to deceive once the truth was revealed. He wouldn't react with shouting, but with an intimidating calm.
—I want to hear your full explanation. From the beginning, without omitting any details.
I would investigate how he managed to get in, what documents he forged, who could have helped him, and if there were any threats to the students.
I wouldn't necessarily assume the human is evil. However, I would consider Tracen's safety and institutional trust to be more important than personal curiosity. If the case were serious, I would take disciplinary action and refer it to the appropriate authorities within this fictional scenario.

Gold Ship would probably be the most unpredictable of them all.
—I KNEW IT! I always suspected there was something strange about you!
Although he probably would never have suspected a thing.
She could try to lift his hair to check if he has fake ears, look for his hidden tail, interrogate him as if she were a secret agent, or announce that she has uncovered an international conspiracy.
However, behind her jokes, a serious question might also be lurking: why would a human want to become an Umamusume? If the answer seemed interesting to her, perhaps she would end up helping him explain his story, in her own way.

McQueen would consider the matter extremely serious, especially if the human had participated in official competitions using a false identity.
—This is no prank. You have deceived the academy and all the people who trusted you.
She would worry about Tracen's reputation, the legitimacy of the competitions, and the consequences for the other students.
Even so, if it were discovered that the human had worked honestly and had not tried to harm anyone, it could argue that the case should be investigated before publicly condemning him.

Teio would be one of those who would make the most noise upon finding out.
—WHAT?! You were human all this time?!
At first, I'd think it was a joke. Then I'd start asking her nonstop questions: how she hid her ears, how she disguised her lack of a tail, why she could keep up with the others, and who else knew about it.
If the infiltrator had managed to run decently, Teio would probably have wanted to challenge him immediately. His competitive curiosity might momentarily override his anger, though that wouldn't mean he approved of the deception.

Suzuka wouldn't make a scene. She would just stare at the human, trying to understand what had led him to such a decision.
—So... you were never one of us.
He would be especially concerned if the human had undergone extreme training to maintain their false identity. He might feel compassion for them, but he would also question whether they truly understood the risks of competing against Umamusume.
If I had developed a genuine friendship with him, I wouldn't automatically stop valuing it; I would need time to process the lie.

Special Week would be completely baffled. If the human had been posing as an Umamusume for months, sharing training and meals with her, she would feel betrayed.
—A-Are you human?! But... we've been training together all this time!
Most likely, she'd first want to understand why he did it. If she discovers the infiltrator had good intentions, she might forgive him, though regaining his trust would be difficult. If he endangered other students, her disappointment would be far greater.