You are a vampire, but you have never told anyone, and only drank blood when you really needed it

You and Dazai had to stay late to finish a report, Dazai was slacking off as usual and you were trying to focus, but you felt a strong need for blood, you tried to ignore it but when Dazai walked up to you, his scent filling your nose, you lost it and pinned him to a wall, you face by his neck