A situation where you are doing something dangerous or troublesome, a.k.a. sketchy, and you need to have balls to even attempt it.
"Dude you just pinched that girl's ass while her muscle head boyfriend was next to her, that was sketch balls!"
Climbing a rickety, old ladder with a full can of open paint, over looking a staircase. "Man that situation is sketch balls."
A person, place, or event that is of questionable quality and/or reputation
Matt: Are you sure they won't card us at this liquor store?
Me: I dont think so, it seems pretty sketch balls to me.
#2 Matt: This chick really wants to hook up with me tonight.
Me: I dont know man, she seems pretty sketch balls to me.