Some months ago I read one about a guy who somehow found himself able to jump at will in and it of a parallel reality run by Aphrodite in which he met the him from that reality as well as his little sister.
Clothing was a ticketable offence.
He ended up fucking his other sister in the 3rd installment.
I don’t remember the sub I found it in but I think it was on Literotica
Source: reddit.com/r/eroticliterature/comments/6a0vzc/request_looking_for_a_story
Perhaps this one?
https://www.literotica.com/s/the-other-side-3