Cramps.

Because shooting blood out of yourself every time you pee wasn't enough.

So we have to get our insides torn apart every month by little period fairies.
*COUGH COUGH*
DEVILS

AND OF COURSE YOU GET CRAMPS AT THE WORST TIMES.

LIKE THEY EITHER WAKE YOU UP
OR
THEY MAKE YOU WANNA CURL INTO A BALL AT SCHOOL
DURING PE