Relationships
Howard is consistently depicted as the most sex-crazed of the guys. For example, he develops a mathematical formula for the likelihood of his having sex by applying and modifying the Drake equation to include the "Wolowitz coefficient", which he defines as "neediness times dress size squared". He states, "I'm a horny engineer... I never joke about math or sex".
Howard's techniques in approaching women are varied, including magic, card tricks, ventriloquism, and techniques from the Mystery Method, such as peacocking and negging.
Along with Leonard and Raj, Howard also attempts to date Missy, Sheldon's twin sister. His offer is not accepted, although it was clear she was waiting for Raj. Katee Sackhoff appears as herself in "The Vengeance Formulation" where she is fantasized as Howard's dream girl. She appears again in season 4, in the same role.
Since the beginning of the series, Howard shows an interest in Penny, but the interest is primarily sexual and she always turns him down. After yet another approach by Howard, Penny finally confronts him about how he treats women. This greatly affects Howard and he falls into a depression, missing work and staying home. When Penny apologizes, Howard tells her about his past relationships and Penny shows some sympathy for him; after her comforting words, Howard tries to kiss her, but she reacts by punching him in the face. With the situation resolved, Penny believes they have come to an "understanding", but Howard instead thinks he was merely "half-way to pity sex" with her.
Howard engages in a "friends with benefits" relationship with Leslie Winkle, which brings him a few benefits besides sex. However, he still becomes depressed when Leslie dumps him some time later. In order to cheer him up, Leonard and Raj take Howard to Las Vegas and manage to hire a prostitute for him.
When the guys travel by train to a symposium in San Francisco, Howard gets a chance to talk to Summer Glau (portraying herself). His clumsy attempts at impressing the actress fail, despite his being in a confined environment with her for multiple hours.
During a camping trip with Leonard and Raj, in which they all get stoned by eating cookies laced with a drug (likely marijuana), Howard reveals he lost his virginity to his second cousin Jeanie after his uncle's funeral. This fact prompts incessant teasing from Leonard and Raj.
Despite the fact that Howard is undeniably obsessed with women, some believe him to be in a homosexual relationship or bromance with Raj. The belief is proposed by Dr. Beverly Hofstadter, Leonard's mother. She says she believes them to be in an "ersatz homosexual marriage". Both Howard's and Raj's parents are aware of this; when Howard asks his mother if Bernadette can stay over, she clearly states she cannot say no when Bernadette is "willing to give the milk away free." She concludes her statement by saying "Frankly, after all your sleepovers with the little brown boy, a girl is a big relief.", while Raj's mother stated "the closest thing we have to a daughter-in-law is that Jewish boy Howard!" Raj and Howard have several arguments during the series, in which Raj repeatedly accuses Howard of leaving him for everyone who is only slightly better looking, which appears Raj to be assuming the cliché female role in partnership arguments. However, Raj and Howard's relationship is mostly close. Raj often whispers comments to Howard when Penny is in the room, which allows him an avenue of communication, given Raj's chronic inability to speak to women (although he was cured from it at the end of Season 6).
In recent seasons, Howard is in a romantic relationship with Bernadette Rostenkowski (Melissa Rauch). A waitress paying her way through graduate school for microbiology studies, Bernadette is introduced to Howard by Penny. At first she and Howard do not get along, as they appear to have nothing in common. However, when they find out they both have overbearing mothers they immediately feel a connection. They are particularly pleased that it could enrage both Howard's Jewish mother and Bernadette's Catholic mother to find out their kids are dating. They also each note that they lost their virginity in Toyota vehicles. Subsequently, Howard realizes Bernadette represents a real opportunity to develop a lasting relationship and, in an impulsive manner, he proposes to her. Although Bernadette rejects his offer, they remain a couple for a time.
There is often a running gag between Leonard and Howard mocking Raj for still being single. In The Plimpton Stimulation, Howard briefly mentions that he and Bernadette broke up a couple weeks earlier, but did not mention it since he "was waiting for the right time". It is later revealed that the relationship ended because Bernadette caught Howard having cyber sex with "Glacinda the Troll" on World of Warcraft, who is later revealed to be played by a male employee of the university (Steve Patterson, "The greasy old fat guy in Facilities Management"). By the end of the episode, the two discuss their problems and restart their relationship from the beginning.
Season 4 introduces Howard's "latent homosexual tendencies" when George Takei appears as himself in an imaginary conversation with Bernadette and Katee Sackhoff over his relationship status with Bernadette and his sexual fantasies with animated characters, which is a reminder of what Leonard's mother earlier says about the ersatz marriage.
In, "The Herb Garden Germination", Howard once again proposes to Bernadette, this time in front of his friends. To the horrific dismay of Raj, who had developed feelings for Bernadette, she accepts. However, during their engagement, Bernadette is awarded her Doctorate degree and reveals that she has gotten a job at a pharmaceutical company which promises a "buttload of money." Although he claims to have supported her new career, Howard's friends mock him for not having a Doctorate, with Penny calling the others doctors then remarking that Howard knows a lot of doctors. The situation reaches its breaking point when he and Bernadette have an argument after she buys him a Rolex. He interprets it as a sign that she will be the main breadwinner.
The souring of relations grow worse when he learns from Raj that, in addition to having slept with Penny, Raj also was writing love poems and fantasizing about Bernadette and him Bernadette, which leads to Howard distrusting Bernadette and believing that she may cheat on him with Raj.
More recently, Howard accepts that Bernadette may be the main breadwinner in their relationship, since they've agreed that if they have kids, he will stay at home with them while she continues to work.
At his bachelor party, a drunk Raj describes Howard losing his virginity to his second cousin, his Las Vegas prostitute experience and their three-some with a pudgy Sailor Moon girl at ComicCon which Wil Wheaton uploads to the Internet. Bernadette picks them up and is furious after seeing the video and is wondering how she can marry a man that she doesn’t seem to know, though she does forgive him after he gives an beautiful apology for Penny to transfer, which send her into tears.
Bernadette tells Howard that she wants to be married to him before he is launched into space. After an abortive attempt to be married at city hall before it closed, they agree to be married on the roof of the apartment building. Bernadette is escorted down the aisle by her father and is married by Raj, Leonard, Penny, Sheldon and Amy who all became ministers for the occasion. The ceremony is photographed by an orbiting satellite for the Google Earth website.
During season 6, the newlyweds do have some bumps including Howard readjusting to being back on earth,. moving out of his mother's house. and spending too much on his collectibles hobby., but they continued to grow a steady relationship together. .
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