During a torrential downpour, Kang Seo-jun, a centuries-old spirit cat, is on the verge of transforming into a beast. He happens to come into contact with Yoon Hae-sol, a student in the Department of Physical Education, who passes by by chance, and unexpectedly forms a fateful bond with her. Upon discovering that Hae-sol's body temperature is the only cure, Seo-jun lies about having "contact deficiency syndrome" and disguises himself as her senior to sneak into the physical education dormitory. "You must hug me once every day." Thus begins an intensive one-on-one lesson involving constant physical contact, all because of this outrageous condition. As the two spend more time together, their feelings grow deeper and deeper, until they can no longer be stopped.