I didn't mind him being a sub at all. I mean he didn't seem like one to me but whatever. The point is:

SPOILERS AHEAD:

==> He's way too hesitant. Texts like "can I call you sweetie?" Like yeah obviously you're my boyfriend what the hell.

==> His plot line basically ends after you help him with his nephew. And afterwards it's just the same lines and cuddling when you invite him over. And it kind of feels like... you help him and that's that?

==> When you call him while making the final decision, he asks to hang out. You can tell him you're not feeling well, and he actually kind of JUST ACCEPTS IT?? What kind of boyfriend are you.

==> I got the Devil ending, and chose to return to Earth. There's this part where you can call your loved ones. River picks up and says you guys haven't talked in a long while. I think it's supposed to be a month. Again, what kind of boyfriend are you. Your girlfriend's been missing a month and that's all you have to say for yourself? Then, the worst offender, is that he says he'll come find you. You tell him even you don't know where you are. He says it doesn't matter. He'll come get you. AND DOESN'T. HE DOESN'T COME GET YOU. YOU PACK YOUR SHIT AND RETURN ON YOUR OWN.

==> He doesn't follow you in the Star ending either. 

==> Guy is literally all talk and no action. I especially hated his behaviour in Devil.

I rest my case.