Continuity mistake: After Lionel and Professor Willowbrook finish talking Clark shows up to talk to the professor. As they talk, while the camera is behind Prof. Willowbrook, he has bright sunshine on his suit coat. When the camera is behind Clark the light on Prof. Willowbrook's right shoulder is gone.
Continuity mistake: When Clark sees that Jeremiah is in the loft, Clark stands up and closes the book he was reading as he says "What are you doing here?". The very next shot from behind Clark shows that the book is back to being open.
Visible crew/equipment: When Jeremiah has just stabbed Clarke in the barn, after he goes down the steps and the camera follows him walking away you see the back of one crew member's head and then a second crew member's, starting in the bottom right of the screen. Just before scene cuts to black you see the first crew member turn his head to the left. (00:26:46)
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.