God's domain.

So when they get on Jabberwock Island he's so confused because he,,,, is no longer a vampire???? He can eat human food again and the sun is no longer making his skin feel icky and he's no longer having cravings for blood. He needs to BREATH now and nearly suffocated once because he forgot he needs to do that. His heart is BEATING AGAIN.

He does question it. A lot. But isn't until the Despair Disease that the whole human thing starts becoming a problem, as age starts gaining on him. His body starts to get older, weaker, and Monokuma says that's his disease but Kazuichi knows better. He's getting old because he wasn't meant to be young and alive. Not as a human.

Everyone demands answers when Kazuichi doesn't get better once Mikan gets executed, but Monokuma insists that every pacient has been healed and Kazuichi doesn't tell them the truth. Who would believe him, anyway? A vampire that got robbed of it and forced to be a human again? That the years he has lived as a vampire where caching up to him?

So when they get into the Fun House and Monokuma demands a kill before anyone could eat and escape... Kazuichi wants to live. He still does have a lot of vehicle to repair and there's that rocketship he has been working on for decades now and the human world keep on changing and he wants to watch it do that and and and he still didn't experience what's love, not since when he was sixteen and still a human and was dating a girl that, now thinking of it, was looking too much like Sonia Nevermind— But he's aware that, even after escaping, there was no going back for him. He would die of old age. And the people around him, the ones he got to call his classmates during the whole ordeal, still have a full life in front of them. One that Kazuichi has lived already for too many times.