Enju is the young, blonde-haired, blue-eyed doll craftsman who runs a doll shop alongside his assistant, Shirosaki. His appearance is notable for bearing a striking resemblance to the legendary doll maker Rozen, a fact that underscores his deep personal connection and rivalry with his former master. A quiet and dedicated artisan, Enju leaves the customer service aspects of the shop to his assistant, preferring to spend his time in his workshop focused on the creation of his dolls. Though he can occasionally display a bitter temperament, he is profoundly serious about his art, known to offer brief words of reassurance even to his unfinished creations.

Enju's primary motivation is a deep-seated jealousy towards his master, Rozen. Driven by a desire to surpass the legendary craftsman, he dedicates himself to creating a doll that can best Rozen's own work. This ambition leads directly to the creation of Barasuishou, a doll he views as his masterpiece and treats as his own daughter. His role in the story is as an antagonist, as he orchestrates events to allow Barasuishou to compete in the Alice Game, aiming to collect all the Rosa Mysticae and prove his superiority over Rozen. He is often accompanied or observed by the mysterious entity known as Laplace's Demon, though the exact nature of their alliance remains ambiguous.

His key relationship is, without question, with his creation, Barasuishou, who addresses him as Father. While he is mercilessly cold and critical of his failed creations, discarding them without respect, his dynamic with Barasuishou reveals a deeper, more complex bond. Despite his ruthless strategy for her to win the Alice Game, he also expresses a seeming admiration for Rozen's doll, Shinku, commenting on her beauty and ferocity as a combatant. Enju also has a connection to Jun Sakurada, who visits his shop and becomes conflicted by the doll maker's unfeeling treatment of imperfect dolls, contrasting sharply with Jun's own experiences.

Throughout Rozen Maiden: Träumend, Enju appears as a mysterious figure whose true identity as Rozen's apprentice is gradually revealed. His character development culminates in the final episodes when his plan backfires. After Barasuishou successfully collects multiple Rosa Mysticae, she is unable to contain their immense power and her body begins to crumble. In this moment, his cold obsession with surpassing his master shatters. He desperately begs Barasuishou to spit out the Rosa Mysticae in a frantic attempt to save her, revealing that his pride as a craftsman is secondary to his care for his creation. Ultimately, as Barasuishou disintegrates in his arms, Enju cries out in despair, and both he and the remains of his doll disappear together in a brilliant flash of light, leaving their final fate unknown.

As a doll maker, Enju's notable abilities are his exceptional craftsmanship and his understanding of the mechanisms that govern the Rozen Maidens. He is skilled enough to create Barasuishou, a doll powerful enough to pose a serious threat to Rozen's own creations in the Alice Game. While he does not possess supernatural powers himself, his knowledge of the N-field and the rules of the Game allows him to manipulate its events from behind the scenes, acting not as a direct fighter but as a master strategist and creator. His workshop is where Barasuishou is both created and, ultimately, meets her end.