When a boy/girl gives a girl a head getting all the blood in there mouth and thenthe girl gives the boy/girl a blowjob and gets cum in her mouth then they kiss and mix the contements
This is when you kiss a women after licking her out, while she's on her period. The period blood should collect in your mouth and during the kiss you pass it onto her.
NOTE: If you wanna try this be aware that you can actually catch HIV from doing this as you're swaping blood.
When you have sex, when the gurl iz on her period. Both partners suck the gurls blood and the boys cum into their mouths, and then they french kiss then swallow the remenants.