Actually it is even worse. MC is important just because Rae says he is, and he lives on just because Rae likes it that way...What initiatives does MC consciously take? Except to peep at the shower and things like that, when girls allow him, I mean. How he makes the plot advance? He only says "yes" to initiatives that the girls propose. And he only gets laid because of the succubus "aura", apparently... Also, it seems that he doesn't know about half of the things that happens in the house around him with the girls. He's the MC but he's not even the most important person in the house. Rae is. He's important just because he, for some unknown reason, has a power that he even doesn't understand or knows where it comes from. The girls need him to be able to go out of the house. If not, he could stay in her room and die, and the girls would just continue their lives. That's not an attractive MC to play as.
And yes, MC has such an uninteresting life that he doesn't even care about what he left behind. His life isn't even interesting for him!
The whole thing is pretty crazy when you think about it. Except for Rae and maybe a bit Lyriel, NONE in the house has slightest idea about the what is going on, and everyone get their information (indirectly) from Rae.