one who is often threatening, (generally in a physical manor), yet does not follow through with such threats; the individual is in fact, afraid of physical confrontation.
One who is "spooked," as in being in fear of something.
One who is "jumpy," or otherwise nervous reagarding any situation.
a person who is so uptight that even the most innocent things done to them seem wrong
Zack saw the band Poison the Well in concert, and the security guards there were so restrictive, their lead singer called them cock-ass bitches, and so the whole band was thrown out of the venue, he later mentioned on a message board.