Popular Big Bang Theory Characters We Wound Up Hating By Show's End

"The Big Bang Theory" (2007-2019) dared to ask the question: Would audiences laugh at a show where every punchline was a joke about how weird and unattractive nerds and geeks are? The answer turned out to be a resounding "Yes!" Throughout its run, "The Big Bang Theory" was a ratings juggernaut even as the list of questionable things it tried to pass off as humor got bigger and bigger.   

The centerpiece of the show was the relationship between aspiring actress Penny (Kaley Cuoco), and the group of scientists/engineers/all-around-geeks who lived or hung out in the apartment opposite from hers. Chief among them was Leonard (Johnny Galecki), who nursed a hopeless crush on Penny, and his roommate Sheldon (Jim Parsons), the most insufferable genius you could ever hope to not meet.

Despite his issues with social interactions, Sheldon's personality changed for the better over the show's 12 seasons. Unfortunately, the same cannot be said for a lot of other characters on "The Big Bang Theory." Here are the characters, some of whom only showed up for a few episodes, who started out fairly likable and then became rather unbearable by the end of their time on the series.  

In the final season of "The Big Bang Theory," Sheldon and Amy (Mayim Bialik) discover a brand-new branch of physics relating to "Super-Asymmetry." The only catch is that it will be decades before Sheldon and Amy's theory can be confirmed with real-world results. Then they discover that a couple of scientists named Pemberton (Sean Astin) and Campbell (Kal Penn) have already found a way to confirm their theory.

At first Amy and Sheldon are excited to meet the two men who helped confirm their theory. Pemberton and Campbell also seem like nice guys at first as they are thrilled to meet Sheldon and Amy. They freely admit that they do not even understand the concept of Super-Asymmetry, and the results of their own experiment would have been a mystery to them if a colleague had not shown them the papers Amy and Sheldon published regarding the ground-breaking discovery. 

And so, Sheldon and Amy think they will be teaming up with Pemberton and Campbell to win the Nobel Prize for Physics for their discovery. But then the latter duo start claiming — in front of the media — that they alone are responsible for theorizing about and proving Super-Asymmetry. It takes a long and hard-fought battle for Sheldon and Amy to show they were the ones who came up with the theory, and that Pemberton and Campbell simply got lucky with their results. 

In "The Wiggly Finger Catalyst" (Season 5, Episode 4), Raj was going through yet another bout of being single and hating it. Penny gets sick of hearing about how miserable he is and fixes Raj up with a deaf girl she knows named Emily (Katie Leclerc), figuring that Raj's selective mutism wouldn't be a problem for a girl who couldn't hear him.

At first the relationship goes well. Emily seems sweet and understanding, and Raj quickly falls head-over-heels in love with her as is his habit. After dating for a few weeks, Raj's friends begin to notice that he is spending huge chunks of money to buy Emily presents. Things get so bad that Penny has to tell Raj's parents about his reckless splurging. Mr. Koothrappali and his wife confront Raj, and force him to choose between Emily and the monthly allowance they give him.  

Raj chooses to stay with Emily, but she dumps him after learning that he can no longer afford to buy her presents. Once again Raj is left crying and broken-hearted. Emily played a return date in "The Emotion Detection Automation" (Season 10, Episode 14) where she told Raj that his biggest problem was that he allowed his parents to dominate him. She also informed him that she was dating a new fabulously wealthy man, indicating that she has not given up on her gold-digging ways.

While all the other characters on "The Big Bang Theory" settled down and found love, the writers of the show could never seem to decide on a girl for Raj. The one who got closest to the mark before everything fell apart was Emily Sweeney (Laura Spencer), who first showed up in "The Friendship Turbulence" (Season 7, Episode 17).  

At first Emily seems almost too good to be true. She's gorgeous, funny, understanding, and seems genuinely fond of Raj. She even accepts his many personal foibles instead of reacting to them negatively like so many women before her. But as Emily started appearing on the show more regularly, her perfect façade started to crack.

She was revealed to have a twisted sense of humor that Raj often found disturbing. Emily also initially and unnecessarily saw Penny as a rival for Raj's affections. After she and Raj broke up, Emily tried to emotionally manipulate him until he put his foot down. When Emily made her final appearance in "The Emotion Detection Automation," she hinted that she had dumped Raj because she did not enjoy his performance in the bedroom.

In the annals of "Girls Raj Struck Out With," let's add another name to the list. Lucy (Kate Micucci) was a fellow geek whom Raj met at the comic book store in "The Tangible Affection Proof" (Season 6, Episode 16). She seemed as awkward as Raj, but the two managed to strike up a conversation that turned into a first date.

Like Raj, Lucy was an extremely shy and underconfident person. This seemed adorable at first, until Lucy ditched Raj on their first date by climbing out of the window in the women's washroom. It turned out that Lucy was not shy so much as pathologically avoidant, to the extent that she had trouble developing new relationships or being with another person. At first Raj thinks his own neuroses are the perfect complement to Lucy's social anxiety issues. 

But no matter how hard Raj tried to make things work, Lucy proved again and again that she was a flight risk. She kept breaking up whenever Raj tried to take their relationship to new levels. Finally, Lucy ended things with Raj for good, and his feelings of heartbreak over the situation were so extreme they helped Raj overcome his selective mutism. Even the perpetually-peppy Penny was so disgusted by how Lucy ended things with Raj that she shouted at Lucy in public in "The Itchy Brain Simulation" (Season 7, Episode 8).   

The writers of "The Big Bang Theory" seemed to take a perverse pleasure in making Rajesh Koothrappali as pathetic as possible in later seasons. And considering Raj started out in the series as a shy, awkward guy who could not talk to women, it's quite impressive how the writers were able to plumb even more lows for the character to sink to later on. 

It started with the constant jokes about Raj's sexuality, from him enjoying wearing a Catwoman costume in public, to making lots of gay innuendo jokes regarding Raj's relationship with Howard. When Raj learns that getting drunk allows him to talk to women, he goes overboard and acts creepily toward his dates in a drunken haze. By the end of the series, any merits Raj had as a smart, sensitive, self-made astrophysicist were taken away from him. 

Instead, he was made out to be a clingy, petty loser who depended on his parents' money to get by, and was unable to find someone to settle down with until the very last episode. The character's actor Kunal Nayyar has his own thoughts on the disappointing end for Raj. "I find it quite poignant that the one character that believed in true love so much was the one who didn't, in the end, find it," Nayyar told Metro.co.uk. "It's beautiful! It doesn't have to be so formulaic, that's what I loved about the show — it doesn't have to be a certain way, you know?"

When Bernadette (Melissa Rauch) first showed up on "The Big Bang Theory," the biggest issue with the character was that she was too low-key. Bernadette was sweet and friendly and sympathetic, and the perfect foil for Howard's larger-than-life would-be-lady's-man. But after the two got married, Howard became a more low-key (relatively speaking) and temperate character, and that seemed to bring out the worst traits in his now-wife Bernadette.

It started with little things, like Bernadette suddenly becoming rather sharp-tongued, not just with Howard but the other characters as well. The explanation given was that Bernadette used to be a babysitter, who can become a strict disciplinarian when the occasion demands it. But gradually, that strictness turned into full-on bullying, to the point where it is revealed that her office colleagues are terrified of crossing her.   

Not only does Bernadette become a bully, but she is shown to be perfectly aware of the fear she invokes in her colleagues and her friends — and she enjoys it. The character also starts bragging about her high-paying job, shading Howard for not making as much money as her, and generally rules the roost at home and at work. Bernadette learns to calm down a bit after becoming a mom, but bits of her past aggression still manage to leak out from time to time. 

In the beginning of "The Big Bang Theory," Penny was set up as every man's fantasy. She was beautiful, but not stuck up about it. She was also genuinely kind and helpful, who did not mind helping the shy and awkward Leonard as he fumbled his way around asking her out and eventually dating her. 

Despite their differences in personality and interests, Leonard and Penny ended up in what seemed to be a loving marriage. But that soon began to change as the marriage progressed. It seemed to start with Penny learning about Leonard's insecurities regarding women stemming from his relationship with his mom. And then Penny also started making more money than Leonard as a salesperson for a pharmaceutical company. 

Suddenly, Penny's attitude toward Leonard changed from loving and supportive to bullying and overly critical. She no longer even tried to hide her contempt for Leonard's more nerdy hobbies, and threw away his prized toy items without consulting him. Penny was also revealed to have been a bully in high school, and that bullying nature started to extend to the other members of the gang. Many jokes are also made about Penny being a borderline alcoholic, and many viewers did not like the way Penny proposed to Leonard once in a drunken haze, and then acted angry when he appeared to hesitate because of her inebriated state.