Among the members of the Japanese Coast Guard, only 1% are certified as divers. Daisuke has decided to become one of them and is partaking in the training course to get his license. In the strange and surreal world found underwater, he puts his life into the hands of his partner Hajime Kudo. Are they just casual buddies or will they become best friends? Live 20-year-old Daisuke's youth with him in this volume!