Rapunzel and Eugene Fitzherbert are the main couple of "Tangled". Rapunzel is the long-lost Princess of Corona with magical golden hair, who desires to escape her tower to experience the outside world while Eugene is a notorious thief known as Flynn Rider.

Rapunzel is the long-lost princess of Corona who was abducted during her infancy by Mother Gothel as Rapunzel had gained the magical powers of the Sun-Drop flower that possessed the power to heal the sick and injured and restore youth and beauty and has since been held prisoner in a remote tower. Eugene is a handsome and dashing thief known as Flynn Rider who broke out of his orphan upbringing for a life of adventure. Rapunzel and Eugene unexpectedly first met when Eugene stumbled upon Rapunzel's tower as he was escaping from the palace guards after stealing the crown of the lost princess. Frightened, Rapunzel knocks out the intruder, but gains the idea to finally achieve her life long dream of witnessing the floating lights that appear only on her birthday by having Eugene take her to the kingdom and in exchange she will return the crown. With no other choice, Eugene agrees and although he tries to convince/trick Rapunzel otherwise, he slowly finds himself becoming impressed with the headstrong young woman. Rapunzel and Eugene begin to grow closer as the film progresses, especially when they learn each other's full backstories.

Rapunzel and Eugene soon begin to develop romantic feelings for each other. The budding romance between them grows stronger on the day of Rapunzel's birthday when they spend the entire day together, exploring the kingdom of Corona. By nightfall, after Rapunzel achieves her dream and witnesses the release of the lanterns, Rapunzel and Eugene finally realize they have fallen in love with each other and almost kiss until Eugene sees his former partners, the Stabbington Brothers at shore. Deciding to abandon his life as a thief and start a new life with Rapunzel, Eugene returns the crown, only to learn the brothers want Rapunzel after learning of her hair's magical properties. Eugene is knocked unconscious and captured by the guards while Rapunzel is tricked into believing he abandoned her and returns to the tower. However, they both later discover the truth, learning of the Stabbings plot with Gothel. With the aid of Maximus the royal horse and the Pug Thugs, Eugene breaks out of prison and travels back to Rapunzel's tower to save her.

Eugene is shocked to see a captured Rapunzel and shortly after is stabbed by Gothel. Desperate to save him, Rapunzel promises to stay with Gothel forever if she allows her to save Eugene. However, refusing to let Rapunzel stay a prisoner, Eugene sacrifices his chance to be saved and cuts Rapunzel's hair, causing her to lose her powers and Gothel's death. Eugene later dies in Rapunzel's arms, but not before they both confess their love for each other. A heartbroken Rapunzel cradles Eugene in her arms, but miraculously learns her tears contain the last of her healing powers, restoring Eugene to life. The couple are happily reunited at last and return to Corona where Rapunzel is reunited with her birth parents after learning the truth about her origins. Rapunzel assumes her rightful place as the kingdom's princess and begins a relationship with Eugene after he is pardoned by the king and queen for returning their lost daughter.

In "Tangled: Before Ever After", six months have passed following the events of the movie and Rapunzel and Eugene have settled into their new lives together with Rapunzel assuming her official role as princess and Eugene now living in the castle. Rapunzel and Eugene have developed a strong and loving relationship and are happily in love, but is met with disapproval by Rapunzel's new handmaiden, Cassandra. Unknown to Rapunzel, Eugene is planning to propose to her, ready to spend his life with her and someday start a family. However, unknown to Eugene, Rapunzel is still struggling to adjust to her new life, feeling pressured to live up to royal expectations. When Eugene finally proposes, Rapunzel realizes that although she loves him with all her heart, she does not yet feel ready for marriage and instead wants to live the life she has always longed for.

Rapunzel rejects Eugene's proposal, but is left with great guilt and later secretly sneaks out for some downtime. Eugene goes to apologize to Rapunzel, assuring he only wanted to keep the love and relationship they have together. However, Eugene discovers her absence and sets out to find her, only to be shocked when he reunites with her the next morning and discovers the return of her newly restored long hair. Eugene is further hurt when Rapunzel refuses to reveal the details of the previous nights events and when he tries to seek answers from Cassandra, he is met with none and is scolded for not realizing Rapunzel's struggles. By the end of the movie, Rapunzel and Eugene reconcile and promise to take their relationship slow.

In "Tangled: The Series", Rapunzel and Eugene have develop a strong, loving, serious and supportive relationship and while they briefly struggle over Rapunzel's secrecy in the return of her hair, their relationship is quickly mended when they promise to keep no secrets and become more open and honest. Throughout the first season, Rapunzel and Eugene are always there for each other in times of need and always offer advise, guidance or comfort whenever the other is troubled or uncertain. Eugene stands by Rapunzel's side as she continues to deal with the pressures of royalty, but also her quest to learn the truth of her hair's return. Rapunzel also comforts Eugene as he deals with his insecurities and doubts with himself at times and his new role in Rapunzel's royal life. Rapunzel and Eugene also show their protectiveness of each other, refusing to leave the other in times of danger.

In the second season, Rapunzel and her friends leave Corona and begin a journey to finally uncover the mystery behind the Black Rocks. Throughout the season, Rapunzel and Eugene's relationship continues to grow significantly at various points and even reach a new milestone in regards to their thoughts on marriage. Following an encounter with an old foe, Rapunzel and Eugene come to understand each other's perspectives of their future together with Rapunzel finally realizing she truly wants to marry Eugene and spend her life with him and Eugene willing to wait until she is truly ready to settle down. Throughout the rest of the season, Rapunzel and Eugene continue to hold a steady and stable relationship. By the end of the season, however, Eugene becomes worried of Rapunzel's safety as they get closer to the Dark Kingdom and their goal to seek out the Moonstone, but especially after he learns of an alarming prophecy that one of their friends will betray Rapunzel.

Eugene is determined to protect Rapunzel, unable to bear the thought of anyone hurting her. However, when the couple are later separated upon their arrival to the ominous kingdom, Eugene makes a shocking discovery about his past, learning he is the long-lost Prince of the Dark Kingdom and meets his father, King Edmund who is determined to stop Rapunzel from seeking the Moonstone. Combined with the discovery of his past and the fear of losing his true love, Eugene decides to aid his father and prevents Rapunzel from acquiring the Moonstone. However, Eugene is left to face great guilt and conflict over his actions and feels uncertainty within himself, believing he doesn't know who he is anymore. Fortunately, Eugene comes to fully support Rapunzel, believing he unwittingly fulfilled the prophecy and helps his father understand and accept her destiny. Eugene and Rapunzel are happily reunited and are ready to face the Moonstone. However, the season ends in a shocking cliffhanger as the prophecy is fulfilled when Cassandra betrays them and fuses herself together with the Moonstone.

In the third and final season, Rapunzel and Eugene's relationship remains strong as they both continue to support and comfort one another. Eugene supports Rapunzel as she struggles with the aftermath of Cassandra's betrayal and Rapunzel encourages Eugene to reconcile and build a relationship with his father, King Edmund. Throughout the season, Rapunzel and Eugene's love grows stronger as they sign the Book of Hearts to officially declare their love and Rapunzel even prepares to propose to Eugene, but find their engagement must once again be put on hold until they deal with the current crisis with Cassandra. Aside from their relationship further progressing, Rapunzel and Eugene continue to grow themselves as Rapunzel finally begins to fully accept and embrace her royal destiny and Eugene is later promoted to Captain of the Royal Guard. Eventually, after Corona is finally at peace following the defeat of Zhan Tiri and Cassandra's redemption, Rapunzel and Eugene at long last finally get engaged in the series finale.

In "Tangled Ever After", Rapunzel and Eugene at long last finally get married.