Tessa Young begins her first year of college by moving into her dorm room with the help of her mother, Carol, and her boyfriend, Noah. During this process she meets her new roommate Steph and her girlfriend Tristan. The day after, Tessa shares a brief encounter with Steph’s friend, Hardin Scott.

The following day Steph persuades Tessa to attend a party where she meets her other friends: Zed, Molly, and Jace, and meets Hardin for the second time. The group play truth or dare, which reveals Tessa’s virginity; she is dared to kiss Hardin but refuses. Later on at the party Hardin attempts to kiss Tessa, but she rejects his advances and leaves.

The following day Tessa meets with Landon, a classmate she met on her first day of classes, who reveals to her that he and Hardin are soon to become stepbrothers, with his mother engaged to Hardin’s father. Following a class debate Hardin again approaches Tessa and insists they start over, inviting her to a nearby lake.

While they swim, Hardin kisses Tessa, saying that they cannot remain only friends. Later, they encounter Molly and Zed at a diner, following which Tessa promises to tell her boyfriend about the kiss she shared with Hardin. He tells her not to do so, saying that he does not date, disappointing her.

Noah surprises Tessa with a visit, and they experience an evening together around a bonfire. In a game of ‘suck and blow’ at the bonfire party, Jace purposely fails in order to kiss Tessa, making Hardin jealous and leading to a physical confrontation. While Noah sleeps in Tessa’s bed after the party, she leaves to check in on Hardin, who has destroyed the house in a drunken rage. She comforts him and they kiss.

The next day Tessa returns to her dorm to check on Noah who, realising her affair with Hardin, leaves her, heartbroken. Tessa and Hardin finally decide to date, but her mother threatens to cut her off financially if she continues the relationship, believing him to be a bad influence.

Hardin finds an apartment for them to live together in and they attend his father’s wedding reception. He reveals that his father was a drunk and his mother was assaulted by some men his father provoked while intoxicated. Tessa comforts him, and they head back to their apartment where she loses her virginity to him.

Later, Tessa grows concerned about the text messages sent to Hardin by Molly; she attempts to confront him, but he dismisses her and leaves. After leaving the apartment searching for him, Tessa finds him at a diner with Molly, Zed, Steph, and Jace. Molly cruelly shows Tessa a video from the first party they attended, revealing that he pursued her as a challenge and intended to make her fall in love with him before breaking her heart. Hardin attempts to convince her that his intentions changed as he got to know her, but she ends their relationship.

A heartbroken Tessa returns home to reconcile with her mother and Noah, who both forgive her. In the weeks that follow, she cuts ties with Steph and her group of friends, eventually interviewing for an internship at Vance Publishing. Before Tessa leaves college at the end of the semester, her lecturer hands her an essay written by Hardin, in which he confesses his love for her; after reading it, she returns to the lake to meet him.