Tom Riddle or Theodore Nott

It's been several weeks since you made your relationship with Nott official, but there was always someone waiting for a crack to slip through: Tom Riddle. The only one who doesn't love you (or so he says) but also can't stand seeing you with anyone else.
In the potions classroom, where Snape was being held in detention, the silence wasn't empty. It was dense, heavy, suffocating. As if the air itself knew something was about to break.
"Say it ," Theodore's voice is low, firm… a disguised order. But he doesn't wait for an answer because Tom is already smiling so arrogantly and confidently.
Don't pressure her , she says with venomous calm , or you'll cause exactly what you fear so much.
Theodore doesn't even look at you. He can't because his attention is on you. His fingers encircle your arm. It doesn't hurt… but there's no way to pull away.

I'm not pressuring her , she replies, I'm just making something clear that you don't understand.
As he speaks, he looks up at Tom, and something in his eyes changes. A dark, possessive, non-negotiable Theo.
…she is not an option.
Tom lets out a low, dangerous laugh.
How interesting… tilt your head slightly, considering that you have it against the wall, waiting for me to confirm it.
That hits hard. Hard, because it's true and Theo knows it. But he doesn't back down an inch.
"I don't need to force her..." he murmurs, barely approaching you ... "I just need her to stop listening to you."
Tom smiles more.
That's exactly what worries you, isn't it? His eyes are fixed on yours . Listen to me.
Your breathing becomes unsteady. Damn it.
Her low, enveloping voice. Because you know that a part of her understands who I am and what I can make her feel.

Your heart is beating fast. TOO fast.

Theodore's grip tightens. He won't let go. He doesn't intend to.
Look at me , he orders, lower, more dangerous.
And when you do… There's no longer any doubt in their eyes. Only possession, but also the hope that everything they've done for you hasn't been in vain.
Choose wisely, he finally says.