Looking fo story, kid gets home finds out parents are swingers they let him have sex with the other couples wife
Looking fo story, kid gets home finds out parents are swingers they let him have sex with the other couples wife
DelawareDan has a series about a college-aged boy who visits home one weekend only to discover that his parents regularly host swinger parties to which his older sister is invited but he isn't. He takes part in secret for a bit, but is upset by the secrecy.
There's a lot of drama to the whole thing and some rather uncomfortable connotations which the protagonist is understandably upset about but which get "handled" pretty quickly.
https://storiesonline.net/a/delawaredan
The two main stories are Taking My Spring Break in New England - Part One and the sequel Taking My Spring Break in New England - Original Ending (in progress). The title of the second is a reference to I Forgot to Call which is a short version of the first story but with a happy ending.
FamilyMan has several stories where the son learns that his parents are swingers.
Swinging Surprise is the one I like best.