It seems dumb at first glance but the truth is he fell in love with Mizuhara so he refuses to force himself on another girl, otherwise that's only thinking with your dick and it's just a shallow relationship.But anyway, yeah, so rental girlfriend because he can't get a real one - and then here's a girl who is actually willing to be his girlfriend, to have sex with him, to give him children - and he's turning her down in favor of his fake relationship.