Hiroyuki, a young man living with his childhood friend Hinata and her mother Haruka, harbors a secret passion for the latter. Struggling with loneliness and a distant husband, Haruka finds herself drawn to Hiroyuki's earnest feelings, leading the two into a risky, clandestine affair. As they indulge in their forbidden attraction, they must navigate the tension of keeping their relationship hidden from Hinata.
Hiroyuki and Haruka's forbidden affair escalates when they risk a clandestine encounter in their workplace break room. Their recklessness is witnessed by Koharu, a cunning coworker who captures the act on camera. Now, Hiroyuki is trapped in a dangerous game of blackmail as Koharu threatens to expose their secret to Haruka's daughter, Hinata.