Omar Quaalude is the lead singer and lead guitarist in his band which also stars Angel ( The pianist), Stretch (second guitarist), and Dizzy (The drummer). Omar's "race" is also speculated to be a dog or a rat. However, given the size difference between the 'rodent' races and the "dog" races (e.g. The Sipper Brothers; Toad, Sleazy, and Zip), this provides some theories that he is a rat.
Omar is a punk. He is constantly putting up an indifference front towards everyone, even to his own bandmates and love interest. He always wants to be in the spotlight and gets outraged and sometimes violent towards anyone who attempts to take it from him (e.g. when Manager Mylar closed the curtain on his song, Omar threatened to bash his skull in with his guitar if he didn't let them continue).
Omar is very selfish and doesn't care who he hurts or humiliates when he doesn't get his way. (e.g. during the Drat's performance, Omar left the stage during their band's second song because it wasn't his song). He is shown to go out of his way to anger Mok after the legendary rocker invited them to his home to discuss a partnership with Angel. There has also been a debate on if he has actually cared about anything else except his fame. Many viewers complained he didn't fit the movie and he should have had a much different personality than the one he was scripted.
When it comes to relationships, Omar doesn't have very many. He often puts up a front of indifference towards everyone and his punk attitude has a tendency to off-put everyone around him, even his own friends dislike putting up with him at times. However, Omar does seem to show more care towards Angel.