Rebecca is Bert's girlfriend who appears in "The Separation Agitation"
Overview
Rebecca is introduced when she and Bert arrive at Apartment 4A.
She is a stunning blonde who was a former actress that became a personal trainer and is much younger than Bert. When Penny asks if Rebecca has dated a scientist before because she was thinking of starting a support group, Rebecca says she dated a Scientologist. Sheldon quips that Bert is copying Leonard because he is dating a woman better looking than him. In response, Amy sends Sheldon out of the apartment for a time out. Rebecca questions if she'd done something wrong and Leonard says it's just normal Sheldon. Bert mentions that he and Rebecca met online to which Raj remarks that he has not had much success with online dating. After Sheldon makes another remark, Amy sends him back out. However, after Bert explains that he matched with his soulmate, Rebecca, only five minutes after he updated his profile and added "Recent $625,000 MacArthur grant winner", Amy calls Sheldon back. After Bert leaves, Sheldon compares them to Leonard - Bert's money and his groveling to get the girl and Leonard says it's completely different - Bert's money will run out but he can beg till he dies. Penny quips, "all that and he's shorter than me."
Back at the cafeteria the next day, Sheldon tells a joke about Richard Feynman, Einstein, and Schrödinger. Raj and Leonard react slowly, but eventually laugh. Bert joins them. He is worried about what everyone said about him being used. He says something about the relationship that Sheldon thinks is funny and tells Leonard it's his turn to tell a joke.
Bert turns up at the apartment to tell them he broke it off. Raj tells him he did the right thing, and begins to compare Bert to his own story which gets increasingly depressing and says that maybe someone else should speak. Amy is glad, but Bert is upset. Sheldon has a go at her and Amy makes a rule that Sheldon should raise his hand for permission to speak. Penny tells Bert he should be looking for someone who likes him for who he is, not what he has. Sheldon raises his hand and Penny makes the mistake of letting him speak because he insults Leonard again. Penny looks to Leonard for support, but Leonard simply looks up at her and points out that Penny gave him permission to speak. Bert then leaves saying he might buy Rebecca a jet ski to get her back. The episode ends with a "Fun with Flags" retrospective and a call comes through from Bert saying the jet ski worked.