Betraying My Perfect and Beautiful Childhood Fiancée, I Fell in Love With My Devilish and Naughty Older Sister

Hayato Hashiro is an honor student. His family is a prestigious big conglomerate, his grades are reasonably good, and he is good at sports. But no matter what he does, he can never be the best. He has a childhood friend who is his fiancee. She is a kind, perfect, and beautiful genius girl. No matter what she does, she is the best. However, Hayato has a strong sense of inferiority to his fiancee and feels suffocated. Then, an older half-Japanese girl named Chiharu Maria moves into Hayato’s house as his stepsister. She is a beautiful girl, but she is also devilish and naive. The free-spirited Maria aggressively approaches the younger Hayato, taking baths with him and sleeping in the same be...