"Bijin de wo Kanemochi no Kanojo ga Hoshii" to Ittara, Wake Ari Joshi ga Yattekita Ken.

After a casual comment to his family, Iori Shino (virgin) suddenly became engaged to Tendou Tsukasa, a girl famous around campus for being rich and undeniably beautiful. But she was also rumored to be a loose woman who would "sleep with anyone." At first, Iori was confused by the difference between