Ushiro no Seki no Gal ni Sukarete Shimatta.: Mou Ore wa Damekamoshirenai.

A high-school boy named Sandai, who prefers solitude, helps a classmate named Shino after she falls into a ditch near his home. He allows her to shower and lends her clothes, despite having no prior interaction with her. Afterward, she begins acting like his friend, seemingly showing interest in him, which surprises him due to her popularity. Unbeknownst to him, Shino has never dated a boy and struggles with social interactions with them. She finds it easy to talk with Sandai, making him develop feelings for her over time. Their growing connection alters the course of his life.