"You don't understand," the villain hissed. "Loving me will ruin you, you stupid thing. Maybe you want that, maybe you want to be ruined and left unstable and hurt, but you don't seem to realise the extent. I will take all the light you can give me and let you burn to ash, even though I can see it'll kill you. I will not blow you out. I'll take it, selfishly, and I'll exhaust you until you hate me. I—"
The hero trapped them against a wall and kissed them, and kissed them more, and then some more until the villain was pushing against them dizzily and the lack of air crumpled their lungs up.
Then, the hero let go.
The villain slumped against the wall, staring, reeling, gasping in precious air.
"I don't care," said the hero. Just as breathless. "I don't care, I really don't. You think we're bad for each other? Then let's just exhaust each other until the novelty wears off. Until then," the hero kissed them again, harder, shorter, and the villain couldn't suppress their noises, "I'll just take what I can get."
The villain didn't have a response to that.
The hero kissed them again.