Sketch off
To be present in a group of friends or acquaintances, and suddenly disappear from said group, never to be seen again that night.
"Dude, I was talking to you last night, and then you completely disappeared."
"Ah, sorry man, I sketch off at the worst times. I'm going to the doctor next week to see if I have sketcholepsy"
"Ah, sorry man, I sketch off at the worst times. I'm going to the doctor next week to see if I have sketcholepsy"