I am sorry you were shoved into this with the worst person ever, John, because kaneki sure wants to go through that gate.

Luckily(?) he is not human and can do very well in a fight, so he'd tell John he'd protect him if he wants to come, BUT!! kaneki will not force him to go along at all.

But Ken wants to see who is singing and where this thing leads to, he's just that type of person who doesn't like to stay still.