Hojin has long harbored a deep affection for Giltae, the kind neighbor who has looked after him since childhood. Unable to confess his true feelings, Hojin's clumsy one-sided love remains a secret, until one night he finds himself masturbating over a drunken, sleeping Gil-tae. Despite the significant age gap, what began as a hidden desire is about to cross a line from which there is no turning back, forever changing the innocent bond they once shared.