Most any kind of blenny.
The picture that hooked me was a blue one perched on the mantle of a blue maxima looking at the camera. Blennies are really cool becuase they like to perch and watch you out side.
And oddly the single most personable fish Ive ever seen was a damsel. It would follow my finger around the outside off the glass like it was a magnet. It was in the marine biology lab back in highschool. For some reason It liked to play chase with fingers. up and down, back and forth.