Second-Hand Reverse Threeway

The act of having an indirect three-way through means of either kissing or engaging in sexual intercourse with one individual, as well as someone who they engage in the same practice with. If person A engages in intercourse with person B, and person B engages in intercourse with person C, then person A, B, and C had a Second-Hand Reverse three-way.

Golly Gee, Brian just had a Second-Hand Reverse Threeway with his ex and her new boyfriend. That's gross!