With contributions by cumhardy. - Thanks!
Wow. This is one I can't believe, except there are videos. Sigh. One person is giving the other fellatio: at the moment of orgasm, the blowee punches the blower full on in
the face, which gives them a bloody nose, and they have blood and semen
emerging from their mouth... and the red/white earn the name strawberry
The only thing I can say- when you punch someone whose mouth is around your cock, they might bite down. I hope they do.