Someone decided to make a parody of Nintendogs, called Nintengirls. There's two covers out there. This one, and this one. There are screenshots too: 1 2 3.

It's fake. The screens are from the game Sexy Beach 2.

Tecmo is working on a game, Touch de Rakushou! Pachi-Slot Sengen Rio de Carnival. Given that this is actually hosted on Tecmo's official server, this one looks legit.

Then there's Lapis, a game that was entered in the Montreal Game Summit 2005 Game Design Challenge. The theme was "sex" and the designer, HEather Kelley of Ubisoft Montreal, designed a game where you stimulate a bunny rabbit by rubbing it's nose the right way.

The way you play with the bunnies in order to win is patterned after the VARIETY of female sexual response

This is the overall pattern but it can?t be achieved in the same way every time — different things work for different bunnies, at different stages of the game

For instance you may need to use tickling at first, and then humming into the ears. But after a while that stops having an effect, and you have to start tapping on its nose.

The site supposedly has an online demo for you to try out, but it requires some obscure plugin that I wasn't willing to try out. Also note that the game was intended to be playable on the DS, but currently is PC only.