In the gymnasium of Higashi-Tama Eighth Elementary School, an AED lecture is being held for sixth-grade students.Facing the children who seemed unwilling to listen carefully, Makino (Matsushita Kohei) told the preciousness of life, but Riko (Nakamura Yuki) told Kei (Okamoto Nori) that "Makino killed the patient"Deep memory.

The children who heard the conversation between Kei and Riko began to spread some irresponsible words, such as “cannot go to the health room” and so on.Shinoya (Morikawa Aoi) pointed out that Makino's usual words and deeds may also be one of the reasons, but Makino didn't listen at all.Under this circumstance, Riko, who had unbearable abdominal pain, sneaked into the empty health room and was discovered by Makino.

Because Riko had other physical discomforts besides abdominal pain, she ignored Kai's advice and asked Makino for help.

Makino sensed Riko's uneasiness and once again explained to the children the dangers of ignoring the condition.During this time, fourth-year Yuugo (Yuda Yuki) suddenly clutched his chest and collapsed...!
Makino immediately carried out emergency treatment, but there was a secret hidden behind the pain in Yonggo's chest.