A feminine version of "jerkoff", a female behaving in a manner which is difficult, obtuse, aggressive, entitled; generally like a jerk. Not whining or grumbling so much as actively causing a problem.
There are others here whose opinion is just as valid as yours; quit being a herkoff and listen up!
Somebody who swamps a conversation, party, anything in fact, with meaningless concocted made up shit just so that there's a lot of crap about with the name hercolena on it.
Gerry says he got his name on so many Urban Dictionary definitions he thought he was superb. Then along comes this hercolena and all the editors got so pissed off they just dissed all the defs with that name on.