Hatsukoi ga Amai Mou Ai ni Kawaru Toki

Reona Mizuno returned to her old high school as a modern literature teacher. There she found her old crush Yuki Nagasako, also working as a PE teacher... and she suddenly woke up next to him one morning after drinking too much at the welcoming party! He was the man of her dreams back then, but he seemed to harbor some feelings for her too...? A reunion love story between a patient PE teacher and a shy Japanese teacher. (Source: Bunkasha, translated)