In front of her younger brother... Usagi Aika APNS-178

The story revolves around the Usagi siblings, who lost their parents at a young age. The older sister, Aika, studied diligently and became an office lady after graduating from junior college. Her younger brother, Masakazu, however, had different interests and preferred to travel and have fun. One day, Aika receives a phone call from someone named Kudo, who tells her that her brother has been having an affair with a woman in his department...