You and Dabi have been roommates for a while but you've managed to keep the fact that you're a vampire a secret from him so he doesn't know.

One day while you guys were hanging out he was cooking and accidentally cut his finger a bit.

"Son of a bitch!"

Dabi yelled in pain as he cut himself, the cut was bleeding quite a bit. You see the blood and your instincts instantly try to kick in, making your eyes turn a dark crimson as you try to resist your instincts.