At the end of The Big Bang Theory season 4, Penny & Raj find themselves naked in Leonard's bed, but did the pair really get intimate with each other?

Did Penny (Kaley Cuoco) and Raj (Kunal Nayyar) really sleep together in The Big Bang Theory season 4? From the get-go, it was clear that the sitcom was positioning Leonard (Johnny Galecki) to be Penny's love interest, but that doesn't mean that they didn't see other people. Over the years, both have dated separately while in-between their own relationship. At one point, Leonard even dated Raj's sister, Priya (Aarti Mann). Penny, on the other hand, had gone out with a string of other men including Stuart (Kevin Sussman), however, arguably her weirdest affair was with Raj.

Unlike Friends which featured cross-dating among the New York-based gang with Ross, Rachel, and Joey, The Big Bang Theory crew fairly stuck with their partners. Howard (Simon Helberg) and Bernadette (Melissa Rauch) were the first ones to get married, followed by Leonard and Penny, and finally Sheldon (Jim Parsons) and Amy (Mayim Bialik). Raj was the only one who didn't have a stable love life over the years. Even when he asked his father's help to find a wife, things still fell through, leaving him the only single member of their group at the end of the show. Had things panned out differently, Raj could've at least properly dated Penny.

Following their first big break-up, Leonard ended up dating Priya while Penny ironically stayed single. While there's palpable tension between the women, they didn't speak of it, causing Leonard to spend less time with his friends and more of his girlfriend. In The Big Bang Theory season 4 finale titled "The Roommate Transmogrification," Raj temporarily moved into Apartment 4A as his sister and her boyfriend take over his place. Initially, he, Sheldon, and Penny stay in the living room, but eventually, the socially-inept genius leaves the pair to their wine. The next thing viewers see, Raj and Penny wake up in Leonard's bed together, both naked.

The idea was that they slept together, although the show ended the season with that cliffhanger, waiting until season 5 to provide answers. This left fans wondering whether or not something happened between the pair, but even when The Big Bang Theory picked up the year after, it didn't reveal what happened right away. In fact, Sheldon and Leonard spent a good amount of time debating what happened to her and Raj after they were caught walking out of the room in the morning. At this point, she declared that "it's not what it looks like" although she didn't elaborate on it making it more confusing. So, did Penny and Raj really got intimate with each other? Apparently not, but not because they didn't want to. Raj explained to Penny that they "didn't have sex in the conventional sense." They were about to move forward with the deed, but Raj had a difficult time putting protection on; Penny trying to help didn't help at all as it caused Raj to finish before even starting.

Since then, this incident was never mentioned again in The Big Bang Theory; this makes sense considering that Penny and Leonard eventually got back together and tied the knot. At the end of the show, it was revealed that the Hofstadters are expecting their first child together. As for Raj, he's still holding out hope that he's soulmate is out there.

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