Literally: Toes of monkeys.
Really: What sucks when an event/thing/person is bad.
Dude, that concert sucked major monkey toes!
I will never go out with him again. That date sucked monkey toes!
This hair-do sucks monkey toes!
That movie that I saw yesterday sucked major monkey toes dipped in carrot juice for thirty-two and a half days exactly (no more, no less) while being danced upon by dingoes in Australia.