A slutgasm is when a slut has an orgasm through anal sex.
Jenny, "Ohhhh! Johnny! i got an orgasm from your penis in my anal!!!! Hump it harder!"
Jenny just had a slutgasm
"That slut last night had a pretty good orgasm"
"We had anal sex"
"I wish I was with her. That slut of yours must look nice naked. Only I was I would have oral and real sex with her, not anal sex. It just feels better"
"Yeah, dude, your right"