Ever since Masaaki lost his father at a young age, Ayaka and Masaaki have lived together. Masaaki came to love Ayaka, who loved him wholeheartedly, more than as a mother. After graduating from university, Masaaki got a job, but his place of employment was in Kansai. Not wanting to leave his mother , Ayaka invited him on a hot spring trip. Masaaki decided to confess his feelings on this trip.