not really that every person in the gangbang needs to be a relative. though it's possible. perhaps a mother with a few sons let's them take a round at her? if not then perhaps just a mother/son ordeal that leads to him inviting his friends. or perhaps a father/daughter where as the father finds out her fantasy of a gangbang and invites his coworkers to take advantage. the idea is hot to me, and I can either write it myself or work with an author. Opinions, Comments? Fire Away
the real one i hinted at local to us was many years ago and involved a dad, uncle, cousin, and boyfriend, with a girl who'd been shall we say,'of loose morals for a long while', she was of course over 18 at this time, (just).