It's character driven... If the girls are written to be open to it I love the harem! But I also feel true guilt if the writer/developer creates a character that actively opposes it... I'm Playing through Ravenous right now... and I actually feel guilty for the interactions with Karina at the point in the story I am...
Good on the writer for making a compelling character to make me feel this way...!
Loyal. And I prefer it when my MC only has one LI in the game. Yesterday I sent Reunion to oblivion (deleted it permanently and sent it to my ignore list) - I'm just not interested in such plots, because 31 LIs is not even absurd, it's outright idiocy.
I'm much closer to VNs like Melody - they have the ability to disperse a potential harem to all the devils.
I prefer games where your main love interest either encourages your polygamy or actually hooks for up with people, so monogamy in the game is not really an option.
I am reminder that in Parental Love, the developer included a Faithful Husband path or some such simply because he felt his game should have it as an optional route. He later declared that it had almost broken him as a developer because he found the monogamous route so boring and tedious and against what he wanted to see happen in the game.
I go with the Thanos approach. Collect and retain as many LIs as i can as long as they are all ok with it. But a hard NO to sneaking around especially if I get even a hint that an LI will find out and get depressed in the future.