A very helpful tipster, Tony, has directed our perverted eyes at an RPG called Ar tonelico that takes child sex (or child-like sex) to a whole other level. Watch for yourself: Go here, then click on "Download" and then "System view." Here's the good stuff from the trailer:
Girl: ... insert it into my back.
Here's another gem, but it's in Japanese. Either way, you get the idea.