2. Someone who finds extra joy in things because they are forbidden.
3. The ideology of opposing convention and boundaries.
A fence in this context represents restricting or directing an individual on where they can go and what they can do. A fence hopper would literally hop a fence to go somewhere else, voice a minority opinion, reject arbitrary rules, break the combo, and screw the rules.
2. I knew that Jo was kind of a fence hopper, so I told her that no one could eat a whole pig fetus in one sitting. I can't believe she did it!
3. You want to host a nude party at a jesuit school? That sounds pretty fence hopper.
Rdawg: Teh Sweetness!! Wanna go fence hoppers right now?
Dudeskie: KK, ill Call Cocoa right now, we'll all jump thru that black guys backyard
Rdawg: Teh sweetness!! wanna go right now!!!
dudeskie: yeah man!!!!
Person 1: You're a bisexual...I'm going to call you a fence hopper.
Person 2: Okay, fine.
Alternate variations using various combinations of the words Border/Fence followed by Jumper/Hopper/Vaulter etc. exist and are also used to the same effect.
Bob: With those Fence Hopper over there.