虽说是未成年，但可不是小孩哟

学业卓著、体育全能的高中生鹤木尚（中岛健人 饰）是学校内一顶一的红人，更是无数女孩倾倒热恋的王子殿下。在他的爱慕者中，有一个稍显特殊的女孩，那就是系出名门的娇贵大小姐折山香琳（平祐奈 饰）。偶然的机缘，让香琳迷上了光彩夺目的鹤木前辈，在内心的最深处，她早已将对方视为非此不嫁的另一半。这一日，香琳从父亲（高岛政宏 饰）口中听到一个令她震惊的消息，那就是在16岁这一年，她将和父亲选定的乘龙快婿步入婚礼殿堂。原本打算抵死拒绝的香琳，很快就发现原来婚约对象居然正是鹤木前辈，这可真是喜出望外的大好事。只是，所谓的命运之恋，并非想象般浪漫而甜蜜。 　　本片根据水波风南的同名漫画改编……On Karin Oriyama's 16th birthday, she receives a present from her parents. Her present is marriage. The person she marries is her first love Nao Tsurugi. He is a popular senior in high school. For Nao, he only marries Karin for economic reasons and in particular the wealth of her parents. Karin loves him truly, but Nao doesn't love her at all. Their marriage is a secret, but Isuzu Ebina, who holds feelings for Karin, learns of their marriage.