Ranmaru Morii (森井 蘭丸, Morii Ranmaru) is one of the main male protagonist of the series. He is considered as "lover boy/play boy" out of the four boys since he always flirts with women. He is also Tamao's fiancé.
Ranmaru is considered attractive by most females. He has red hair and gray eyes. He usually wears a t-shirt with a striped gray cardigan at home. At school, Ranmaru is seen wearing the normal school uniform.
With a rogue's charm and the sex appeal and drive of ten men, Ranmaru chases (and also usually gets) any woman he desires. It should be noted that he can often be clueless about everyday life, and occasionally is viewed as callous. Ranmaru, like his fellow housemates, only allows a select few into his innermost thoughts.
He seems to consider himself an expert as to what will help Sunako become a lady, claiming that a girl needs to be appreciated in order to "shine." He is usually the one who develops what he believes are appropriate ultimate dating scenarios, which usually involve forcing Kyōhei to take Sunako to an expensive restaurant and then to a romantic movie. These plans usually end in failure, as Kyōhei finds it too uncomfortable to go through with Ranmaru's plans.
Like Takenaga, Ranmaru comes from a wealthy family, though his wealth is derived from his family's chain of hotels. His parents moved the somewhat unwilling boy into Auntie's house since they believed that he needed a dose of reality. His family viewed his womanizing nature and lack of reality troublesome and feared those flaws would one day have serious consequences. Ranmaru's initial treatment of his roommates was rather rude, but as bonds formed between the boys he eventually learns better ways of treating people.
Ranmaru's morals have been occasionally debated in the series, since he thinks nothing of sleeping with a married woman. In one story, his paternity to a young boy was questioned, with his initial reaction being seen as sleazy. Ranmaru's ability to adapt (and Sunako's cold treatment of him) led him to treat the child properly, only to discover that he was not the real father.
Oddly enough, Ranmaru is also highly skilled in swordsmanship. Several chapters in the manga indicate that he has never been beaten by either Takenaga or Kyōhei.
Ranmaru is engaged to a girl named Tamao, which was arranged by his parents as they wanted to curb his troublesome, and sometimes dangerous, womanizing behavior. They adore Tamao because she is a true lady who is both beautiful and smart, and they believe she is their son's only hope of steering him on the right path.
Ranmaru is a notorious playboy who is the only child of a wealthy family of hotel chain owners. He is extroverted, confident, and a self-professed expert of love and women, having dated many older married women. However, he has a good heart and cares for his friends and is the most active in the goal towards making Sunako into an ideal lady. He is later engaged to Tamao, a beautiful and weathly but also reserved and sheltered girl, whose unusual attitude towards him creates mixed feelings and makes him unsure of his playboy tactics.
- Main article: Ranmaru Morii/Gallery