In Japan, Monroe Miyabi, a beautiful mother, lives together with her son Satoshi. They lead happy days but have been longing for their husband who has gone abroad on business trip. One day when an old friend of Satoshi named Yu visits them for astronomical observation, he suddenly confesses his love and kisses her. Despite feeling uncomfortable, she can't resist the thrill coursing through her body. Afterward, under pressure from Yu again, she reluctantly accepts another kiss...