The picture needs to be a bit clearer. But judging from the overall head shape and stripe pattern, it seems you have a real fang blenny, Meiacanthus atrodorsalis. The mimic blenny is Ecsenius gravieri (a cool-colored bicolor blenny, if you will) and actually mimics Meiacanthus nigrolineatus. Your blenny's stripe extends abruptly from the eye to the dorsal fin, whereas in the mimic and nigrolineatus, the line trails across the body toward the anterior portion of the dorsal fin.
You can get bitten, but it is harder do than you might think.