The Big Bang Theory started as a simple show about a few socially awkward but brilliant scientists and devoted comic book, sci-fi geeks. In the first episode, they meet the beautiful Penny, who is not the genius that her new friends are. Leonard was instantly smitten, and, over the course of the next twelve years, not only would he find the way to win Penny’s heart; the rest of our heroes had been able to find love over the years. They all came a very long way in those twelve years; Leonard got his dream girl, Sheldon learned all about life and even found his soulmate. Despite being a complete creep, even Howard wound up with a family. Raj was left feeling hopeful, and he would continue his search for true love.

Over the years, we’ve watched our quartet of heroes grow up and become decent members of society, or at least decent by TV sitcom standards. They were able to do that not because of their contributions to science, it was actually because they each had to learn on their own terms how to function in society, which was something that their girlfriends and future wives had a huge part in helping with. Here are five relationships which fans were totally on-board with, as well as five which most viewers rejected.

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Behind: Leonard And Penny

Besides the dynamic between Sheldon and Leonard, the relationship between Leonard and Penny was the nucleus of the entire series. Their “will they or won’t they” from the first season sweetly and mostly organically evolved into a friendship and then from there, a real relationship as opposed to Leonard wishing and hoping Penny would actually love him. Their marriage was the culmination of what a lot of the early seasons was really about.

Rejected: Leonard And Priya

While it was nice to see Leonard expand his horizons past Penny, the relationship between himself and Raj’s sister, Priya. Where Penny was and has always been fairly carefree and actually likes Leonard for Leonard, Priya didn’t seem to like Leonard for Leonard at all.

She put him in new clothes, which wasn’t necessarily a bad thing. But she also demanded that Leonard stop seeing Penny. She asked him to make all of these grand changes to his life, she refused to tell her parents about him.

Behind: Sheldon And Amy

Sheldon and Amy hold each other in The Big Bang Theory.

How could you not root for “ShAmy?” After Raj and Howard meddle for fun and set Sheldon up with a dating profile, he and Amy met at a coffee shop. Over the course of the series—the very, very long course of the series, thanks to both of their moving at a snail’s pace—fans got to experience just about every single first that a relationship could have. Almost once a season, the pair had some moment or another that got them closer to the alter. Once the finally did, it was he big moment fans had been waiting for.

Rejected: Raj And Anu

With all of the main male cast members, plus supporting character Stuart all ran off and got some sort of significant others, Raj was feeling the pangs of loneliness. As a result, he took advantage of his Indian culture and asked his father to arrange a marriage for him. The result was a hotel concierge, Anu.

Anu was just about anything Raj could want; she was pretty, and she didn’t seem to mind Raj’s unhealthy love for his dog... or his unintentional creepiness. But Raj was a character who wanted to find true-blue romantic love, which was something that just wasn’t going to happen with Anu.

Behind: Raj And Just About Anyone

Because Raj was a hopeless romantic, it was hard not to feel bad for the guy when he kept striking out in the dating department, even as his career was taking off. So, any time the guy seemed like he had a shot, it was easy to rally around him.

For a moment, it seemed like he was going to find a soulmate in the equally awkward Lucy. Because she too was scared of talking to people, one of their dates was just the two of them texting. She escaped out a window, but, as far as Raj was concerned, it was proof that perhaps one day they wouldn’t try to leave.

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Rejected: Penny And Zack

When we first meet Penny, she’s not necessarily an airhead, but she sure does pick a bunch of them before realizing that she’d rather date Leonard and be appreciated for who she is.

Zack was one of the mindless buffoons that Penny would date during this time. Thankfully, he treated her fairly well, but that just meant he was a bigger obstacle for Leonard to deal with.

Behind: Stuart And Denise

It was a relationship that fans didn’t know they wanted. But, since it was nice to see all of our Big Bang heroes find some solace and comfort by the series’ end, why not their local comic book store owner?

While he was originally presented a successful business owner, the writers decided that wasn’t funny enough and made him a pathetic loser who, despite having a successful store, has to live in it, and then with Howard for a time. Yet, once he started dating fellow comic book nerd Denise, he stopped being as much of a loser as he was. He still was clueless, but at least he had a girlfriend.

Rejected: Leonard And Leslie

Leslie and Leonard talking on the couch in The Big Bang Theory

The reunion of David and Darlene from Roseanne attracted some buzz when it was first announced that Sara Gilbert would be visiting The Big Bang Theory. As Leslie Winkle, she was the perfect foil to Sheldon and was able to put him in his place.

As far as her relationship with Leonard, it just didn’t seem like it would be fun for the show. All they did for fun was play their instruments and wax on about the possibilities of them dating. Not to mention Leslie knew that Leonard only had eyes for Penny.

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Behind - Raj And Howard

While they technically were not ever an item, and, quite frankly, the idea bothered them a little, Howard and Raj’s friendship was strong enough to be one of the anchors of the series. While they were both creeps at times and Howard was incredibly mean to Raj, their friendship was uniquely sweet. That's why Howard’s impassioned speech to keep his friend from foolishly running off to London to get married worked well enough to get him to stay and try to get his real happy ending.

Rejected: Penny And Just About Anyone Not Leonard

Besides Zack, just about anyone Penny dated was always huge musclebound meatheads. They all usually made Leonard look like a total catch—maybe that’s why she finally realized it. One of her worst boyfriends would be Kurt. He was the epitome of anti-everything the show was going to be about. It was clear he wasn’t going to be around long, just another obstacle in Leonard’s path.

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