Actually, i saw this in
this game. (at market you can click on Deny tits, and they will bounce a little bit). So, I`m not sure about Oni`s skill in that area, but it`s totally possibly to do. Just add variables like "if love=< 300" don`t accept touch(=face slap), "if love=>300" accept touch(=get undress) and trigger text balloon and animation.
The same mechanics goes for undress. Touch button on her blouse/skirt/top and so on, and get a result - face slap or undressing.
For me, this game is great, but i wanna have some "direct" interaction with girls. And also, i think menu is a little bit overloaded with actions.