The Big Bang Theory: 10 Worst Characters Who Appeared After Season One

10. Ramona

Because Sheldon acts like... Sheldon, it was rare for the opposite sex to show any interest in him. That's why it was jarring to see Dr Ramona Nowitzki doting on him and indulging his every unreasonable whim. Because she made him breakfast, gave him foot massages, and tidied his office, everyone suspected she had an ulterior motive.

And they were right. After Sheldon had grown accustomed to Ramona's ways, she pushed him to focus entirely on his scientific work, at the expense of his friends and hobbies. When he finished a paper she helped him with, Ramona made it clear she was sucking up to Sheldon so she could have shared credit on his work. Acknowledging that Ramona was using him, Sheldon said he wanted nothing to do with her ever again.

If you thought Ramona may have learned from her experience, guess again. She appears later in the series, trying to steal Sheldon away from Amy. The fact that this encounter compelled Sheldon to propose to Amy is probably the only good thing Ramona did during her tenure on the show.