On a night of heavy rain, a vacation rental is accidentally double-booked. Unable to contact the management company, married Ren and office worker Tatsuya must spend the night beneath one roof as strangers. Awkward conversation reveals their shared loneliness, and every touch brings their hearts closer. As rain and thunder echo outside, Ren tries to fill the emptiness left by her husband’s overseas assignment, but once their bodies join, neither can stop. Knowing morning will separate them, they drown in the guilty lust of adultery.