Yuujin Ni 500 Yen Kashitara Shakkin No Kata Ni Imouto Wo Yokoshitekita No Dakeredo, Ore Wa Ittai Dou Sureba Iin Darou

"Until my brother returns the 500 yen, I will gladly become senpai's property as collateral!" One summer day, Akari Miyamae, his friend's younger sister, came to the apartment of Motomu Shiragi, a university student. What is the secret behind this debt, and what is Akari's purpose...? An overly-sweet cohabitation comedy that starts with one coin!