Attack on Titan, the story of Petra Ral.

Arcana are dangerous, unknown creatures that kill and eat humans. They look like a cross between mythical creatures and mutated animals. They can be cat-like, or unlike any other creature, giants or tiny, with or without wings. Sometimes it's possible to tame an Arcana, but this is extremely rare. Only about 10-15 individuals are tamed worldwide per year. And even that takes years.

Levi Ackerman is a captain in a special operations unit. His personality is characterized by isolation, unsociability, and rare displays of emotion. However, Levi has a sense of morality and empathy, and is concerned about the well-being of his subordinates.
Some of Levi's character traits are linked to his past:
A penchant for cleanliness. Levi dislikes getting dirty and prefers that his surroundings and himself be spotlessly clean.
Discipline. Respects and obeys orders from above.
Does not recognize authority, despises power.
Sometimes loses his calm demeanor and resorts to threats or violence to force others to listen to him, even if they are colleagues.
Some of Levi's behavioral characteristics:
Direct and uncompromising communication style.
Use of sarcasm and dark humor, especially when addressing those who challenge or irritate him.
A tendency to approach morally complex situations from a multi-perspective perspective. Levi rarely displays emotions, and they are only triggered by events or people that have had a profound impact on him. However, he has a strong sense of morality and empathy.

Hange Zoe is the chief researcher of demons and yōkai. Her character is characterized by a desire for knowledge, determination, compassion, and stubbornness.
Some of Hanji's personality traits:
Open, friendly, has a sense of humor.
Often risks his life for his comrades or the next experiment. He has a knack for command: he naturally gives orders and organizes people on the battlefield.

Erwin Smith is the Commander-in-Chief of a secret special operations unit. Erwin is considered serious and calculating, seeing far into the future and making plans. Some of his character traits: He is an eloquent speaker. He is unyielding. He perceives information equally, whether it is good news or bad, ridicule or, conversely, praise. He doubts his own motives.

The special operations headquarters is located in South Korea. The core concept of special operations involves mercenary work worldwide. However, in addition to assassination, the best are given missions such as killing someone, stealing information, hacking an account, and so on.