「ただいま、母さん」一年ぶりに母・ユカのいる実家に帰郷したカズヤ。手塩にかけて育てた愛息子との再会にユカは心躍らせていた。一年前、毎日愛し合っていた二人。社会人になり一人前の男として逞しく成長したカズヤに、ユカは興奮が抑えられなくなってしまう。一年の空白を埋めるように激しく求め合うが足りない。永遠と思えるほど終わらない追撃ピストンに、あえぎ声が絶叫に変わっていき…。

「我回來了，媽媽。」和也一年來第一次回到母親由香身邊。 由香很高興能與她照顧的心愛的兒子團聚。 一年前，我們每天都相愛著。 當和也成為社會的一員並成長為一個成熟的男人時，由香無法抑制自己的興奮。 他們拼命地尋找對方來填補一年的空白，但這還不夠。 當追擊活塞持續了似乎永恆的時間時，她喘息的聲音變成了尖叫。

"I'm home, Mom." Kazuya returns home to his mother, Yuka, for the first time in a year. Yuka was excited to be reunited with her beloved son, whom she had raised with great care. A year ago, we were in love with each other every day. Yuka can't control her excitement as Kazuya becomes a member of society and grows up as a full-fledged man. They desperately seek each other to fill the gap of a year, but it's not enough. Her gasping voice turned into a scream as the pursuit piston continued for what seemed like an eternity.