greased lemur

Construct used to describe an impossibly difficult and annoying thing to obtain that one immediately regrets upon finally succeeding. Catching a greased lemur is nearly impossible and extremely frustrating. They are slippery and moody and bite. Greased up, they are even more of a nightmare. And when you finally catch it, you have a hairy, exhausted disgusting oily lemur. Great. Hooray for me.

Not entirely dissimilar to a pyrrhic victory.

Dude, she's a greased lemur what are you doing? You're going to hate yourself when you finally get her.