Kaoru Hanabishi is the male protagonist of the story, a university student who lives a quiet and somewhat solitary life in Tokyo. He is a fairly average young man in many respects, neither struggling with his studies nor prone to dramatic emotional outbursts, which distinguishes him from more volatile characters in similar narratives. Kaoru is generally well-liked by his peers and is an active member of his university's photography club. His given name, Kaoru, translates to "fragrant," a reflection of his gentle and kind nature. He carries himself with courtesy but can be direct and forthright when a situation requires it.

Beneath this calm exterior, Kaoru harbors a deeply painful past. He is the estranged heir of the powerful Hanabishi zaibatsu, but his background is complicated by the fact that his parents never married, making him an illegitimate child. Following his father's death when Kaoru was five, the Hanabishi family forced his mother to give him up so he could be raised as the next heir. His childhood was marked by severe physical and emotional abuse from his paternal grandfather, with his back left scarred from being beaten with a bamboo or wooden cane. The final breaking point occurred when his grandfather burned all of his late mother's possessions and photographs; when Kaoru tried to stop him, he was savagely beaten. Shortly after this incident, Kaoru chose to sever all ties with the Hanabishi family, entering a self-imposed exile and vowing never to return.

Before his exile, Kaoru had been engaged as a child to Aoi Sakuraba, a girl from another prestigious family, in a perfectly arranged union. When he left the Hanabishi clan, this engagement was formally canceled by their families. Having lost his family legacy and his promised future, Kaoru began living an average but lonely life, feeling adrift and without purpose until a chance encounter reunited him with Aoi, who had never stopped loving him. This reunion becomes the central motivation of his life; despite his initial perplexity, he quickly warms to the idea of being with her and looks forward to building a future together. However, to avoid shaming her family, they are forced to keep their renewed relationship a secret, a situation that drives much of the story's drama.

Within the story, Kaoru functions as the anchor of a growing household. He lives alongside Aoi and several other young women in a large mansion, where he must navigate a harem-like situation while remaining completely devoted to Aoi. His deep-seated trauma from his family's abuse manifests in his lingering emotional scars and his general discomfort with his past, though Aoi's gentle and unwavering devotion plays a crucial role in helping him heal. Key relationships include his bond with Miyabi Kagurazaki, Aoi's guardian, who initially distrusts him but later becomes a crucial ally, eventually helping him foil his half-brother's plans to marry Aoi for control of the family business. Kaoru is also a source of support for the other residents, such as Tina Foster, Taeko Minazuki, and his childhood friend Mayu Miyuki, who all find themselves drawn to him in different ways.

Over the course of the narrative, Kaoru develops from a reclusive and scarred exile into a more decisive individual who actively fights for his love. He demonstrates significant growth by eventually choosing to permanently abandon the Hanabishi name, legally adopting his mother's surname so he can marry Aoi without the shadow of his family's influence. While his core personality remains consistently kind and reserved, this final act represents a complete severance from his traumatic past and the establishment of a new identity on his own terms. Aside from his kind disposition and loyalty, his notable abilities include his skill with a camera as a member of the photography club, though his most defining trait is his remarkable resilience in overcoming a history of profound abuse and loss.