Tessa’s mother’s greatest wish in life is for her daughter to go to college at Washington Central University, so when Tessa is accepted to WCU she is excited about making her mother proud. However, she is also anxious about whether she’ll make friends in a strange new place. She is surprised that her roommate, Steph, is a hardcore party girl who loves bright makeup and revealing clothing. Tessa also finds herself deeply attracted to Hardin, one of Steph’s guy friends. A young Englishman with tattoos and a rude attitude, Hardin’s rough personality conflicts with Tessa’s niceness and inexperience.
Tessa reluctantly accepts Steph’s invitation to join her at a frat party. She doesn’t fit in well with the crowd at the party. As she wanders around the frat house, she stumbles into a bedroom where Hardin is kissing a pink-haired girl named Molly. The scene makes Tessa uncomfortable, and her night grows even worse when she has to help a drunken Steph, who vomits and then passes out.
Steph’s friend Nate shepherds Steph and Tessa into one of the frat house bedrooms and tells Tessa she can stay there with Steph while she sleeps. Tessa is shocked when Hardin comes into the room, which turns out to be his bedroom because he’s a member of the fraternity throwing the party. Hardin and Tessa get into an argument because he doesn’t allow people in his room.
Tessa leaves and cries in a bathroom because the party is terrible, and she doesn’t know how to get home. When she emerges from the bathroom, Hardin tells her she can sleep in an empty room where he has also placed Steph. Tessa is shocked that Hardin is being nice to her.
On Monday, Tessa excitedly attends her first day of classes and is shocked to see Hardin in her British literature class. He sits by her and they continue their verbal sparring as the days pass. She also meets Landon in British literature class, a normal guy who Hardin irrationally dislikes.
The next weekend, Tessa agrees to go to another party at the same frat house with Steph. Tessa wonders if Molly is dating Hardin, but Steph insists that while Hardin might play around with a lot of girls, he never dates anyone or has one girl who is special to him.
At the party, during a game of truth or dare, people keep daring Tessa to drink shots of vodka. While drunk, she wanders into Hardin’s room and starts reading from his classical book collection. He yells at her for entering his room again. They get into another verbal fight and she leaves.
A guy who is drunk tries to grope Tessa, but when he chases her down the hall, she runs back to Hardin’s room for safety. Hardin comforts her after her scary moment, and she kisses him. They make out on Hardin’s bed while he’s only partially dressed, but Tessa stops suddenly, recalling her boyfriend, Noah. They both feel awkward about the encounter, and Tessa runs away from Hardin’s room yet again, angry with him for being cold toward her when she stopped kissing him and angry with herself for cheating on her boyfriend.
Tessa walks for over an hour until she arrives back at her own dorm, only to discover Hardin waiting for her. Hardin was worried after she left, so he drove around trying to find her. Tessa’s mother and her boyfriend, Noah, suddenly arrive at her dorm to express their concern over her recent increase in party attendance. Tessa feels like she’s being treated like a child but reconciles with her mom and boyfriend, promising them that she’ll stop going to parties.
The next day, Hardin comes to Tessa’s room, supposedly to see Steph, and they end up kissing again. When Steph catches them, she warns Tessa not to develop feelings for Hardin because he doesn’t date. She says that girls often fall in love with Hardin, only to have their hearts broken when he doesn’t return their feelings.
In British literature class, Tessa and Hardin begin yelling at each other, supposedly arguing about the characters of Elizabeth and Mr. Darcy, when they’re actually discussing the details of their own strained relationship. After class, he grabs her arm, and she screams at him to let go. She feels like he’s playing emotional games with her.
Hardin asks her to admit that she’s bored with her boyfriend and excited by him. After more conversation, they agree to be friends. He takes her on an outing that she calls a friendly meeting, and he calls a date. They go swimming in a secluded stream, which he says is his favorite place. As they swim and kiss, Hardin asks her to admit that they can never just be friends. The mood remains passionate when they emerge from the water, and Hardin gives Tessa an orgasm using his fingers. Afterward, Hardin takes Tessa out to eat.
When Noah calls her, she ignores the call and tells Hardin that she intends to break up with Noah. Hardin tells her not to break up with her boyfriend on his account, since he doesn’t date. This infuriates Tessa, who warns Hardin never to speak to her again. Tessa calls Noah to come visit her for the weekend, but when he arrives, she is disappointed by their lack of passion. She can’t help comparing Noah’s bland niceness to Hardin’s intensity.
She gets a phone call from Landon, asking her to come to his mother’s house and help Hardin, who is also there. Tessa borrows Noah’s car and goes to Landon’s house. Hardin has been having a drunken fit.
Hardin’s father, Ken, has been dating Landon’s mother, Karen, for a long time, and Hardin is angry that the two have decided to marry. Hardin resents his father for being wealthy, while his divorced mother has to live in near-poverty in England. Drunk and lonely, Hardin begs Tessa to stay the night with him. She does, and they fool around sexually before falling asleep.
The next morning, Tessa goes back to her dorm to find Noah furious with her for taking his car and staying out all night. Hardin follows Tessa to the dorm and tells her to explain their situation to Noah. Noah guesses that Tessa has been cheating on him with Hardin and walks away crying. Tessa is upset with Hardin for making her tell Noah the truth.
Before long, Noah forgives Tessa and agrees to put the past behind them, if she agrees to stay away from Hardin. However, even when Tessa stays home from the weekend party at Hardin’s fraternity, Hardin shows up at her dorm room to watch movies with her. He says he sleeps better when she’s by his side, so she agrees to cuddle with him in the same bed.
The next day, Hardin wants to go with Tessa on her car-shopping trip, and the two of them run into Hardin’s father off campus. His dad invites them to dinner at his house with himself, his soon-to-be-wife, Karen, and Landon. Tessa accepts the invitation, and Hardin screams at her for trying to help him connect with his father.
Despite his earlier fury, Hardin later accompanies Tessa to the dinner. Karen mentions that Ken is actually the chancellor of WSU, a fact that Hardin neglected to mention. When Ken is surprised that Hardin hides his father’s chancellorship from his friends, Hardin yells that he doesn’t need to use his father’s name or position, then storms out of the room. When Tessa follows him, he insults her. She yells at him for ruining the evening, and then they kiss. Hardin’s mood improves. When he and Tessa return to finish dinner, he apologizes to everyone for his behavior.
After dinner, Hardin admits to Tessa that he wants her more than he has ever wanted another person or thing in his whole life. Tessa realizes this is an admission of his genuine feelings for her, and she kisses him. Hardin performs oral sex on Tessa, and then they return to the dining room. Karen and Ken offer to let Tessa stay the night, since it’s late, and they give her a room across from Hardin’s. In the night, Tessa hears Hardin screaming in his sleep. She wakes him from a nightmare and comforts him, holding him throughout the rest of the night.
When they return to Tessa’s dorm room, Noah is waiting because he was worried when Tessa didn’t answer her phone. In front of Noah, Hardin tells Tessa that he wants to be more than friends with her and that he wants to become a better man for her. Tessa tells Noah he should leave, officially breaking up with him and choosing a relationship with Hardin. Now that they’re together, Tessa is plagued by worries that Hardin will cheat on her with Molly, since he and Molly have had a physical relationship in the past.
Hardin’s father sets Tessa up with an internship at a publishing company. She’s thrilled to accept the part-time job, and Ken has only one request for her: try to persuade Hardin to attend Ken and Karen’s upcoming wedding. When she mentions the wedding to Hardin, he gets angry and ends the conversation. They make up and spend the night together in Hardin’s room, with Tessa comforting him when he has nightmares.
Tessa goes to a party at Hardin’s frat house without telling him, because she suspects he’s spending time with Molly. Her suspicions are confirmed when she finds Molly sitting on Hardin’s lap. Tessa begins drinking and joins a game of truth or dare. When she accepts a dare to kiss Hardin’s friend Zed, it makes Hardin angry. Zed accepts a dare to take Tessa upstairs alone for 10 minutes, but since she’s drunk, he doesn’t take advantage. Instead he asks her on a date, and she agrees. The next day, Hardin and Tessa get into a fight in front of Steph and Molly, and Hardin yells that he loves Tessa, which she refuses to believe.
Tessa realizes that she loves Hardin, but goes on a date with Zed. In British literature class, Hardin and Tessa get into a fight about the characters in Wuthering Heights, who reflect their own tempestuous relationship. Tessa goes to a bonfire party with Zed and kisses him again but can’t stop thinking of Hardin.
When she goes to Hardin and admits to him that she loves him, he tells her that he loves her more than anyone in the world. They spend a day with Karen and Ken, which passes without any major arguments. Tessa is hopeful that Hardin will attend the wedding.
Tessa’s mother visits her at her dorm room, furious that Tessa has broken up with Noah. Tessa’s mother doesn’t approve of Hardin and insists that she will cut off financial support from Tessa if she stays with him. To ease Tessa’s concerns about losing her dorm room if her mother withdraws support, Hardin suggests that they find an apartment and move in together. As their relationship deepens, Tessa decides she’s ready for an even closer physical connection, so she and Hardin have sex. Afterward, Hardin takes the bloody sheets off her bed and says he’ll throw them away for Tessa.
At the mall, they run into an unpleasant acquaintance of Hardin’s named Jace. Hardin warns Tessa to stay away from him because he’s a bad person. Hardin works harder to persuade Tessa to buy an apartment with him and she finally acquiesces. Tessa and Hardin are excited about their decision, but the happy mood is ruined when they go to Hardin’s frat house and run into Jace, who seems threatening.
Jace wants to play a party game. When Tessa joins in the game, she ends up kissing a stranger named Dan. Hardin witnesses the kiss and fights Dan. When the fight is broken up and Hardin calms down, he and Tessa argue, and then have sex.
Tessa and Hardin go to look at apartments and accept one that suits Tessa’s taste exactly. They sign the contract, and Hardin agrees to pay for the rent while Tessa pays for the utilities. They settle into life in their new apartment, enjoying the privacy until Hardin ruins the mood by not coming home one night.
Tessa is so worried about what kind of trouble he might have gotten into, she gives him an ultimatum: He has to improve his behavior or she will leave him. Since she also requests to know the cause of his screaming nightmares, he tells her that when he was a child, he witnessed several men raping his mother and that the event still gives him nightmares. Tessa comforts him, and their relationship returns to normal.
Ken and Karen’s wedding day arrives, and Hardin and Tessa enjoy the festivities. As they make plans to go to England together for winter vacation, and it occurs to Tessa that Hardin is acting strangely and avoiding his old friend group. She realizes that Steph, Zed, Molly and the others probably don’t even know that she and Hardin are living together. Tessa goes to a biker bar that Steph likes and stops in to visit her old roommate. Hardin arrives at the same bar and is angry with Tessa for coming.
Molly hints that there’s a big secret that the whole group is aware of and informs Tessa that Hardin made a bet with all the other guys that he would be Tessa’s first sexual encounter. In order to win the money they promised him, he showed the other guys the bloody sheets from Tessa’s dorm room and the used condom from their first night together. The money he won from the bet enabled him to make the down payment on the apartment he and Tessa share. Tessa slaps him and berates him for taking advantage of her. Hardin insists that he made the bet before he fell in love with Tessa and that he’s genuinely sorry. Tessa refuses to listen to his apologies and allows Zed to drive her home, asking him to tell her all the details of the bet.