Three young men live and work in a nearly-deserted Japanese city. The three wander the streets, ruminating on the pointlessness of life in the modern age, never quite living up to the deeds of a fallen friend, until one of them goes too far and permanently fractures their relationship.

Aya and Asuka work in the sex industry. Despite clashing personalities, they somehow get along, spending every spare moment chatting aimlessly as they hang out in coffee shops, smoke together outside, or ride together in their work van. One day, the van breaks down, and they find themselves walking through the city at night. Wandering aimlessly and talking, their trivial chatter gradually takes on a greater depth.

In 1970s Onomichi, Akira invites his crush Yoshioka to spend summer break at his home. But when Yoshioka falls for Meeko, tension brews beneath the heat.

Kyoko, a young Japanese girl training to become a professional mermaid, is saved by her coach's mouth-to-mouth "kiss of life". Desire awakens within her, she finds her mermaid voice and discovers the devastating effects of her singing, which will lead her to face the other side of the world.