Shumming

The act of shitting and cumming at the same time.

"Did you hear?"

"Hear what?"

"Tony was shumming all over the toilet yesterday"

"Omg, really!?"

Fumming

Ejaculating into the rectal cavity and proceeding to fart out cum bubbles.

Girl: he really filled my asshole last night, so much so I started fumming
Friend: oh wow!