Is there any hentai game, that is similiar to, for example, viva project? Of course, i dont mean in characters, but in gameplay. That type of games, where you can just do literally anything just to watch how she will react, or something like that. (i didnt played viva project myself, but i saw the pictures and youtube cuts, so idk if it was the right example but at least it is the closest one i remember)

See if you can find a copy of Artificial Girl 3.  If your lucky it'll run on a modern system.  What's odd (and frustrating) about it is that you can't ask the girls for sex. If you can get them in the mood they may initiate an H scene, or they may decide to go and have lunch.