Life seems ordinary for one married woman until her husband drops a bombshell: his stunningly beautiful female cousin needs to stay with them temporarily. Expecting a simple family arrangement, she's unprepared for the immediate, charged shift in the atmosphere the moment the cousin steps inside. The dynamics of their cozy home immediately become tense, filled with a strange and dangerous sexual energy.

The wife quickly begins to feel like a third wheel, unable to shake the unsettling feeling that something intimate is developing. She notices the seemingly innocent, yet undeniably lingering touches between her husband and his cousin, coupled with slow, hungry glances that speak volumes without a single word. Every interaction feels heavy with unspoken desire, setting off loud alarm bells she desperately tries to rationalize away.

Is she just being overly paranoid and jealous, imagining infidelity where there is only familial closeness? They are family, after all. They are just cousins... right? This adult drama forces the wife to confront her fears as the boundaries blur, secrets deepen, and forbidden desires threaten to destroy her marriage in a series of highly explicit encounters she might be forced to witness—or even participate in.

Alternatives: 사촌은... 맞지? (Sachon-eun... Majji?)