Hibiki (Mana Ashida) mistake Shunpei (Hidetoshi Nishijima) and Ruri’s (Yuko Araki) relationship. She runs away from home after seeing the two together.

Shaken by the sudden turn of event, he visits Shiho (Yuriko Ishida). The two decide to work together for Hibiki. They find out she ran off to somewhere unexpected…

Meanwhile, Umi (Riku Onishi) also decides to run away from home after an incident! As the Natsume family scatter to pieces, the truth of 5 years ago slowly comes to light.
Just what happened between Shunpei and Hibiki?