This topic has been discussed a lot, if you search this thread you'll find a lot of info, but, TLDR:
Here the most updated info regarding the scope of porn themes in the game.
As for the
when: the plan is to have in place all the pieces of the base systems and have a bunch of assets to populate the world first, then the focus will shift into making adult stuff and the rest of the subsystems...there is no specific ETA, Matto is working alone on the coding aspect and that takes time, he hopes to have something playable to show by the end of the year and open a Steam page with a proper demo.