Houkago wa Koi no Lesson wo / Kimi wa Saikou no Diamond

A young woman named Mirabelle has married Arthur, her first love and a respected teacher, achieving a dream from her childhood. Despite her devotion and purity, Arthur, who is both intelligent and attractive, refuses to have any physical relationship with her. The story explores the mysteries tied to Arthur's past that prevent their marriage from progressing. The narrative unfolds in a refined and esteemed educational institution, blending two historical romance tales.