Stupidity: When Lois, possessed by Dawn, comes downstairs and says she's going to the prom and Clark is taking her, Clark doesn't think for a moment it could be Dawn. He already knows Dawn can posses others, those people don't act like themselves, Dawn is obsessed with the prom, Lois isn't acting like herself, and Lois is now not only suddenly prom obsessed for no reason, but wants to go with Clark when she said that would never happen.
Stupidity: After the accident, Dawn is in spirit form on the road trying to wave down an oncoming car (driven by Martha Kent). Dawn doesn't know she's a spirit that can pass through objects at that point. Since Martha can't see her, she keeps driving straight towards Dawn. Dawn sees the vehicle isn't slowing down and instead of simply stepping out of the way to avoid getting hit, she turns her back, revealing to the audience that objects can pass through her now.
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.