19-sai no Otto ni wa Himitsu ga Aru

Aina Tanaka is a thirty-something office worker in the secretarial department whose life appeared perfectly mapped out. Engaged to a wealthy heir, she expected nothing but smooth sailing ahead. That illusion shatters when her fiancé abruptly abandons her for a younger junior colleague. Devastated and desperate to numb the sting of betrayal, Aina drinks herself into oblivion and collapses on the street, only to be rescued by a mysterious young man. Their unexpected encounter leads them to spend the night together, leaving Aina terrified that she may have committed a crime. However, the young man quickly eases her fears. After listening to her heartbreaking situation, he reveals that he is about to turn nineteen and proposes a contractual marriage. Eager to prove to her ex-fiancé that she has already moved on, Aina agrees to the arrangement. Yet, when their wedding night finally arrives, she discovers a startling truth: despite his bold proposal, her new husband is a complete virgin with absolutely no romantic experience.