I think "harem" tag is a bit misused. There is nothing wrong with dating a few girls (or guys) before committing to one person. Lot of the time I see players go for one character (usually the one encountered right from the start of the game) before even bothering to check what the other characters are all about. So there is often no need for an actual harem thing. Just explore your options like in IRL but without committing one way or the other. I am not saying bang everyone and see who is tightest before choosing. Like in this game, you get to know the girls without actually being forced to screw them or dating them. Just by being their friend. Optional harem after that is just fine. That's just my opinion, though. Only a couple of games where I liked the harem route because it serves the story well.