Hi !
In Inanna Revenge, you'll inevitably start a relationship with the game's first two love interests (just like Emilie in AlwaysFan). However, all the other relationships are entirely optional and depend on your choices.
Just like in AlwaysFan, you'll be able to decide the nature of your relationship with each character—whether it's romantic or purely sexual. However, Inanna Revenge is a bit more flexible in that regard.
I hope that answers your question!