Continuity mistake: When Chloe shows the newspaper to Jimmy with his photo on it. The photo is not the same when it is shown in the close-up.
Continuity mistake: Lana was found shot in her upper left shoulder but at the end of the show she has a sling on her right arm. (00:42:00 - 00:43:05)
Continuity mistake: When Lana hands the gun to Jimmy, she hands it to him aimed away from her. When Jimmy takes it, it is aimed towards her. (00:59:00)
Continuity mistake: When Chloe and Jimmy find Lana shot in the elevator, there is a gun on the floor beside her, with a small pool of blood beside in the gun. In the next closeup shot on the floor, the small pool of blood is gone. (00:42:00)
Continuity mistake: At the beginning of the episode, we see that the clock reads 2 o'clock. Jimmy then takes Chloe into the back room to his set-up movie date. A little into the scene, they then hear a gunshot. When they rush out, the clock now reads 4:15. However Chloe and Jimmy were not in the back room for this long. At 4:15 they find Lana shot, and call 911. Then after the credits, we return to the scene, but now the police have arrived. But now the clock reads 2:15. There is no way the police would have taken so long, that the clock would have jumped all the way around from 4:15 to 2:15, therefore the continuity on this clock is mixed up.
Answer: No, there is no such character in the comics. He's a "meteor-freak" like all the other baddies on the show. The sound has something to do with him vibrating his vocal cords very fast to create a high-pitched squeal.