(Vampire atsushi)

atsushi was turn into a vampire at a young age, atsushi can goes without blood for a while but needs blood to keep going on.

without blood, atsushi will be very weak and fragile, basically he will be sick but will live. Atsushi only get blood when he desperately needs it.

the armed detective agency knows nothing about atsushi being a vampire, he has told them and atsushi didn't know if he should even tell them anyway.

(You choose what happened next)