The futa content isn't a very large portion of it. Succubi have a futa spell that they can use, and it come up in several scenes, and is occasionally mentioned.
For the harem part of it ... if you don't like harems, this might not be the game for you. All the relationships are very interesting and get their own development, all the characters feel unique, but there are a number of times where you have to sex someone for story reasons. They make sense in context, but you the player don't get the choice.
Ultimately I think the distinction that should be drawn is that "you" the player are not the main character. You are playing as a specific character, who has been around the block and has their own opinions, prejudices, and lines in the sand, and you get to make decisions within the context of his nature. You can't take the story off the rails or do things they he just wouldn't do, or not do things that he would definitely do.
