The sexual act of intercourse where upon two men intertwine their legs and rub their buttholes together, similar to the sexual act of intercourse where upon two women intertwine their legs and rub their vulvas to each other.
When two girls rub their pussies together until one or the both of them have an orgasm. The way they reach an orgasm is because both of their clitourouses together which is stimulating.
When two women are scissoring, one queefs into the other's vaginal opening. The second woman then emits her own queef adding to the volume of the queef. This continues until both vaginas are completely full of fishy air.