Here's why Penny (Kaley Cuoco) dated Stuart (Kevin Sussman) in The Big Bang Theory season 2. Known for her active dating life at the beginning of the sitcom, Penny has gone out quite a lot. It was clear that she had a type before she got together Leonard (Johnny Galecki), which is why their relationship was played out as an anomaly on the CBS show. However, she had a much weirder dalliance when she agreed to go on a date with Stuart.

While the comic book store that he owned already made an appearance in The Big Bang Theory season 1, Stuart's first appearance wouldn't be until season 2, episode 20 titled "The Hofstadter Isotope." Initially an aspiring comic book artist, he changed to a mo re practical career path without veering away from his original passion by opening up the joint that the boys frequently visit to get their superhero fix. In the same episode, Penny went with her friends to the aforementioned shop to look for a present for her nephew, there, she met Stuart for the first time, who asked her out on a date. Intriguingly, Penny agreed to the surprise of everyone.

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The date went well overall, and it seemed like Penny genuinely enjoyed herself — enough for her to invite Stuart into her apartment for a "cup of coffee." Unfortunately, they got distracted when Sheldon (Jim Parsons) caught up with them and started a debate with Stuart that dampened Penny's mood. A couple of episodes later in The Big Bang Theory season 2, episode 22 titled "The Classified Materials Turbulence," it's revealed that Stuart has scored another date with Penny, giving the impression that she might actually be into him, but that's not exactly the case. So, if Penny wasn't truly attracted to Stuart, why did she give him the time of the day when she could've dated other guys?

Big Bang Theory Stuart and Penny

Penny's decision had something to do with her complicated romantic relationship with Leonard. At this point, the pair had already gone out, but their assumed incompatibility burdened them with doubts on whether or not their affair can actually work, although this was more of Penny's issue as Leonard was pretty clear about his feelings for her. At the end of The Big Bang Theory season 1, Penny admitted that she wanted to stop dating bad guys and be with someone who really cares about her — Leonard fit this bill and the pair started going out briefly. However, her insecurities about her academic achievements derailed the budding relationship, making her hesitant to fully open up herself to him.

The problem is, at this point, Penny's time with Leonard made her realize how fantastic it is to be in a healthy relationship with an actual good guy. While she obviously wanted to be with Leonard, she's scared that she'll eventually look down on her because she's not as intellectually-gifted as him. This led her to Stuart instead, who is similar to Leonard in a lot of ways but isn't as intimidating in terms of scholastic attainment.

The truth eventually came out when Penny accidentally said Leonard's name while making out with Stuart. This was after Leonard tried to sabotage their second date by giving Stuart bad pointers, which were essentially the things that he did on his date with Penny. Not knowing why Penny really didn't want to go out with him again, Leonard assumed that she was turned off by the way he behaved during their date. Fortunately, the pair was eventually able to sort things out with The Big Bang Theory finale finally giving them the happy ending they deserved with a baby on the way.

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