A fork of Rural Dictionary
purely and simply an alternative to "fuck". the term most likely came out of the austin, tx area in the mid 90's when austin uber alles experienced its new sexual revolution and casual sex became commonplace. fifteen, then, probably refers to the amount of time a good casual fuck takes- 15 minutes. perhaps the reference is to amount of positions.
we got so horny that we decided to fifteen right there on her parents bed.
To randomly add swearwords to an anime-dub to get a higher rating and attract more buyers. Practiced frequently by Manga Entertainment in the 90's.
Manga Entertainment thought fifteening was the new black.