red play

The act of oral, digital and/or sexual copulation with a female who's menstruating (or a male or female partner who's bleeding rectally), especially when blood is smeared about salaciously.

She called to postpone their hookup date because her aunt Flo was visiting, but he told her "it's cool, I'm into red play".

reds are playing

Your girl is on her period

Bae the reds are playing