Aunt Flo

A euphemism for menstruation. "She" stays for around 5 days every month, can make you feel cranky and emotional, and you count the days until Aunt Flo leaves!

Also featured in the South Park episode "Spooky Fish."

Jade: Aunt Flo has come to visit, she picked good timing!

Melanie: Oh sorry hon.

Stan: I wish Aunt Flo didn't have to visit now.
Randy: Yeah, me too. But she only visits your mom for five days or so. I'll be out sleeping on the couch.

human furnace

When you get into bed with your partner especially on a cold night and you can feel the heat radiating off their body, making for extra cosy warm snuggles to get yourself nice and toasty.

"You're my personal human furnace."