When you get really really drunk and are passed the point of being shit-faced. You get so drunk you are fuckfaced.
To be fuckfaced is hilarious to everyone except the one who is fuckfaced. The one who is fuckfaced usually does something highly embarrassing.
"Dude you were so drunk last night."
"Man no I wasn't"
"Do you even remember what happened?"
"Not really man. What happened?"
"Well you got so drunk that you stripped down, painted your penis and put a costume on it, and walked up to random girls and said 'Don't worry citizen. SuperPenis will save you from the villianous VaginaMonster!' And tried to have sex with them so 'SuperPenis' could save them by pounding the 'VaginaMonster' into submission."
"Dude that's not drunk. I was completely fuckfaced."
"Hahaha yeah you were. And it was hilarious."
"Not to me."
"Well it was to the rest of us."