One guy watches his boyfriend or husband get fucked by another man, and the scene plays up jealousy, humiliation, and power imbalance. The “left out” partner often gets ordered to stay on the sidelines, hold his dick, or kneel nearby while the other two go at it, sometimes with dirty talk about who really owns that ass. It can end with him cleaning up the cum, getting denied, or being allowed a small consolation like sucking the bull off after.