A socialy awkward person who due to obsurd and obnoxious personality traits- such as an obsessive interest in anime and weapons- becomes a social reject. After being tormented their whole life (by more themselves than anyone else with their estranging behavior) they turn "Goth" (note the quotes). They believe that their intensly dark exterior will hide the fact they are complete geeks, this backfires because no one really likes goth people either.
Escentialy, a Gotheek is a fake person who acts a certain way in order to gain attention but is so socialy awkward that they fail in their false exterior as well.
"Hey remember Gurtrude?"
"Yeah, she totaly came back from break and now she's trying to act all 'goth'"
"Does she still carry around those anime books?"
"Yeah, what a Gotheek"
a merge of two stereotypes goth/geek and is either
1. a geek who is generally unique and dark
2. a goth who is better than most with computers or other tech like items
person 1: did u see person 3's new trenchcoat
person 2: yea he's so dark and a little creepy
person 1: yea but he's a beast with computers
person 2: no doubt he's so frickin gotheek