Tooru Honda has always been fascinated by the story of the Chinese Zodiac that her beloved mother told her as a child. However, a sudden family tragedy changes her life, and subsequent circumstances leave her all alone. Tooru is now forced to live in a tent, but little does she know that her temporary home resides on the private property of the esteemed Souma family. Stumbling upon their home one day, she encounters Shigure, an older Souma cousin, and Yuki, the "prince" of her school. Tooru explains that she lives nearby, but the Soumas eventually discover her well-kept secret of being homeless when they see her walking back to her tent one night. Things start to look up for Tooru as they kindly offer to take her in after hearing about her situation. But soon after, she is caught up in a fight between Yuki and his hot-tempered cousin, Kyou. While trying to stop them, she learns that the Souma family has a well-kept secret of their own: whenever they are hugged by a member of the opposite sex, they transform into the animals of the Chinese Zodiac. With this new revelation, Tooru will find that living with the Soumas is an unexpected adventure filled with laughter and romance.

A year has passed since Tooru Honda began living in the Souma residence, and she has since created stronger relationships with its inhabitants Shigure, Kyou, and Yuki. She has also grown closer to the rest of the Souma family and has become familiar with their ancestral secret, having helped them with many of their personal issues. The closer Tooru gets, however, the more she begins to realize that their secret holds a darker truth than she first presumed. Summer is approaching and Tooru is invited to spend her days with the Soumas, mainly Kyou and Yuki. Tooru wishes for an easy-going vacation, but her close relationships with the two boys and the rest of the Soumas may prove to cause trouble. As they grow more intimate, their carefree time together is hindered by older hardships and feelings from the past that begin to resurface. The Eternal Banquet also dawns on the members of the zodiac, and they must tend to their duties alongside the unnerving head of the family, Akito Souma. With the banquet approaching and a plethora of feelings to be solved, will Tooru's life with the Soumas remain peaceful, or will she find herself in a situation from which she cannot escape?

After the accident in which she lost her mother, 16-year-old Tooru moves in with her grandfather, but due to his home being renovated, is unable to continue living with him. Claiming she will find someone to stay with but also fearing the criticism of her family and not wanting to burden any of her friends, Tooru resorts to secretly living on her own in a tent in the woods. One night on her way back from work, she finds her tent buried underneath a landslide. Yuki Souma, the "prince" of her school, and his cousin Shigure Souma, a famous author, stumble across Tooru's situation and invite her to stay with them until her grandfather's home renovations are complete. Upon arriving at the Souma house, Tooru discovers their secret: if a Souma is hugged by someone of the opposite gender, they temporarily transform into one of the animals of the zodiac! However, this strange phenomenon is no laughing matter; rather, it is a terrible curse that holds a dark history. As she continues her journey, meeting more members of the zodiac family, will Tooru's kindhearted yet resilient nature be enough to prepare her for what lies behind the Souma household's doors?

The elite members of Shuchiin Academy's student council continue their competitive day-to-day antics. Council president Miyuki Shirogane clashes daily against vice-president Kaguya Shinomiya, each fighting tooth and nail to trick the other into confessing their romantic love. Kaguya struggles within the strict confines of her wealthy, uptight family, rebelling against her cold default demeanor as she warms to Shirogane and the rest of her friends. Meanwhile, council treasurer Yuu Ishigami suffers under the weight of his hopeless crush on Tsubame Koyasu, a popular upperclassman who helps to instill a new confidence in him. Miko Iino, the newest student council member, grows closer to the rule-breaking Ishigami while striving to overcome her own authoritarian moral code. As love further blooms at Shuchiin Academy, the student council officers drag their outsider friends into increasingly comedic conflicts.