Hikari, unable to have children, lived a blissful married life with her husband. However, her husband's younger brother, Kotaro, had been living off his parents' support. After their parents passed away, Kotaro, now struggling financially, suddenly showed up and moved into their home. Complaining that "no one understands me," he harbored deep insecurities about his worth and abilities. Resentful of his older brother for marrying a beautiful wife and living happily, Kotaro lashed out in frustration, forcefully ■ing Hikari to relieve his pent-up anger.