Kazushi, a university student living alone, is troubled by the presence of two childhood friends, sisters, who hang out all the time at his apartment.

The cheeky older sister, Ayane, and the laid-back younger sister, Kotone.

With the two always around, Kazushi has been semi-forced into a life of abstinence for

a long time... One day, a trivial argument leads Kazushi to take a bath with the sisters in the apartment's tiny bathroom.

Even though he is still wearing his swimsuit, the soft touch of them clinging to his body makes Kazushi's reason waver.

"Huh... you were lonely without me...?"

Ayane and Kazushi are finally alone at the sports festival, where they go to cheer on their sisters, and the atmosphere is good...!

But then Ayane's classmates enter the girls' locker room while they're having a secret rendezvous!?

In a panic, Kazushi and Ayane take refuge in the narrow locker room to avoid being seen. They

spend several minutes pressed together, holding their breath.

Kazushi loses himself in the warmth and heartbeat of Ayane, and the sweet scent of sweat mixed with her...

"My swimsuit is... gone!?"

Kotone's bikini falls off the moment she slides down the water slide at the pool.

Kazushi quickly hides her chest and runs into the storehouse, but the sight of the two of them alone topless is too stimulating for a boy of his age...