Update 02/10/2017
Nightgames is a Java game where you sexfight other coeds in a college campus.

The idea is you and the NPCs wander around on campus, and when you get into an encounter, you try to make each other orgasm until they give up.

It starts off vanilla but then opens up as you progress, unlocking this like succubus, magic, and other content.

The mod adds additional content on top of the original, with most of them dealing with transformation.

You can grow cocks/pussies/tentacles/etc to help you in your fight. It also enables you to play as different genders to start, but it's not as well supported because the original game assumes you are a guy in a lot of places.