If the succubus come, he will desappear? That's why shimizu tie his dick?

no, is just to make him cry

just because he is sadistic. and it's an incubus! ;)

I thought that something would happen with him hahahaha like, he still being hungry even if shimizu fucking him. This make me a little confuse.

I see. I always confuse the terms ╮(￣▽￣)╭

actually yes, he is being starve by shimizu not cumming inside of him.