A female teacher, Reina, decides to let Sakai, a male student, stay at her house after he is unable to return home from school due to a sudden heavy rain. She was planning to spend that day with her boyfriend, but she ended up fighting with him because she gave Sakai to her house. When Sakai saw Reina's sad expression and her huge breasts wet from the rain, his admiration for her and her sexual desire exploded and he attacked Reina. Reina struggles with her position as teacher and student, but she is determined by Sakai's dedication.