Yuka, a married woman living an ordinary life, lives with her husband's younger brother, Masato, who has come to Tokyo with the aim of becoming a stage actor. Her husband comes home late, so Yuka often spends dinner time with Masato. One day at dinner, she hears Masato say, "I have a kissing scene in my upcoming audition, but I have no experience and I'm worried." Having had too much to drink, Yuka thoughtlessly offers to be his practice partner. But the moment their lips touch, she is overcome by a numbing sense of guilt...