A real harem would break the scope of the game, so that isn't in the cards. Some of the erotic scenes will happen during cases and with one-off characters. sometimes with the target of the cases (like in the tutorial case), sometimes with people who can offer some sort of assisstance and sometimes it will be along the line of the female MC "distracting" a guard, so the male MC can slip past him unnoticed (or the other way around, if it's a female guard). These scenes depend on our main characters corruption levels and are just about sex, with no deeper connection between the people invovled.
Outside of that, there's the option to closer relations between our main characters and 3 other characters. For the female MC, it's the male MC (obviously), Sawyer and a yet to be introduced character. For the male MC, it's the female MC (again, obviously), Lydia and another, yet to be introduced character. I might also go for a potential lesbian romance route between FMC and Lydia, but that's low on the priority list right now and depends on how much time and ressources I'll have available.