When you are having sex with a girl and you're on top and you are about to cum, you light her hair (any hair will work) on fire, then you ejaculate into her hair whilst performing the meat spin!

The act of setting someones bodily hair alight and dousing the flames with the use of ones urine or semen

What happens when you get a blow job, and you end up ejaculating so much, that the cum, reaches your arm pit.

Occasionally, it has been known to get in hair as well.