Nakajima is a peculiar, green creature that not even his owners could identify. He is rather large, occupying a good amount of space on the wall of the Glory residences of which he is propped on. With no visible body, he only possesses a large head, and a pair of stout forearms. His head is adorned by 12 petals, all of which he has named, giving him the appearance of a flower.
Nakajima has black eyes and prominent eye bags. And although he is predominantly green, his thin lips are a pale shade of pink.
According to Haru Glory. Nakajima has the tendency to be a "Know-it-all". Despite his goofy nature, Nakajima cares deeply for the Glory kids, and seems to be more knowledgeable on the world than he lets out. He values his petals ("feathers") greatly, and is quite vain about them.
Nakajima welcomes Haru and Cattleya Glory back home, but is taken aback at the sight of Plue. At Cattleya's suggestion that Plue is a dog, Nakajima is further appalled. Later, after Haru runs away as a result of Cattleya's unexpected outburst, the older Glory child confides in Nakajima who comforts her, and assures her that getting carried away by emotions is normal, and no one can be perfect.
After Haru returns home, he inquires about the big city, as well as if the world is at peace. According to Nakajima, it is presently hard to determine where the world stands as it is. The state of the world lies in the hands of the organization known as Demon Card and the Dark Brings. Nakajima explains that while knowledge on Demon Card is scarce on Garage Island, they are quite notorious in the mainland. In addition, Demon Card employs the Dark Bring to wreak havoc, and the world is at the dawn of a full-blown war. Afterwards, Nakajima quickly changes the subject and offers to share about his romantic endeavours. He is dejected when Haru walks away.
Moments later, Nakajima exclaims in panic for the Glory kids to get outside, just as a huge blast destroys the residence. As the smoke clears out, Nakajima assures Haru that he is fine, save for his eight and ninth petals that were blown off.
After the encounter with Feber, Nakajima is enraged when Haru suggests that the rest of his petals be cut off. Days later, Nakajima expresses his adamant disapproval of Haru's decision to become the next Rave Master. Regardless, Haru ignores his pleas, and Nakajima is shocked even more when Cattleya gives her consent. As Haru leaves, Cattleya begins to tease Nakajima, and when the former jokingly proposes marriage, Nakajima is flustered. After Cattleya clarifies the joke, Nakajima grumbles about crazy kids.