Board Thread:General Discussion/@comment-24098614-20160522195522/@comment-25942629-20160528190903

Killing him or turning him into a vampire would be the easiest things to do to keep Yu in control. Trapping him in Cursed Gear is also possible, but they would need the JIDA for that. If Mika weren't there, demon!Yu may have killed someone when he first changed like that without warning. The JIDA's policy is simply to kill people who become demons.

Yu threw his humanity away in Nagoya. His actions are not without consequence.