Having gotten the max relationship with Metatron and Celica, I have found their sex scenes to be adorable, funny, and very well written. I can completely see a Metatron/Sarah/MC threesome down the road! I'd like to see a Celica/Sam/MC threesome just to see if they could, yanno, cooperate on something, but that might end badly for the MC...
I'd noticed that the later boss fights are multi-battle. The fight to save Ina(tm) was a few fights, and the fight against Sofra is at LEAST 4 fights (please tell me I was on the last round with her), are you intending to make most of the boss fights multi-battle? The fight to save Ina made sense, because it was "fended off the goons? Fine, I'm next", but Sofra seems to be either bored or the next boss fight is going to be super tough, given she seems to be taking the MC more seriously each round.
Dorky fashion model succubus teaching out of her element angel about sex I found funny and adorable. :)