Kureno Sohma belongs to the Sohma family and was originally cursed by the Rooster spirit of the Chinese zodiac. His curse shattered unexpectedly around age sixteen, freeing him as the first Sohma to break the zodiac bond, though he concealed this liberation from most relatives. Akito Sohma, the family head, grew deeply distressed by his freedom, fearing the collapse of the zodiac connections. In response, Kureno vowed never to abandon Akito, confining himself to the Sohma estate for years as Akito’s assistant while managing the family head’s responsibilities. This seclusion created substantial gaps in his worldly knowledge; he did not enter a convenience store until age twenty-six.

Extremely polite, selfless, and quietly obedient, Kureno exhibits kindness reminiscent of Tohru Honda, a similarity noted by characters like Arisa Uotani and Saki Hanajima, as he consistently prioritizes others over himself. His sheltered existence fostered a gentle yet naive demeanor, occasionally revealing scatterbrained tendencies—such as spilling groceries during his inaugural store visit due to unfamiliarity with shopping baskets. Despite his gentleness, unwavering loyalty to Akito anchors him, stemming from guilt over his freedom while others remained cursed and pity for Akito’s isolation. This devotion evolved into a clandestine sexual relationship with Akito, which ignited lasting friction with Shigure Sohma upon discovery.

Kureno’s life shifted during a rare outing when he encountered Arisa Uotani at her workplace. A subsequent lunch date sparked mutual attraction, but Kureno deliberately withdrew afterward, citing his promise to Akito, causing emotional pain for both despite his private acknowledgment of deep feelings for Arisa. His internal turmoil intensified as he witnessed Akito’s escalating abuse toward other zodiac members, including imprisoning Rin Sohma—whom Kureno later aided in freeing.

A pivotal moment arose when Kureno recognized his complicity in perpetuating Akito’s toxic dependence. He confessed that his unquestioning obedience enabled her fear and anger, stifling her growth. After expressing his intent to depart, an enraged Akito stabbed him in the back. Recovering from the injury, Kureno chose to permanently leave the Sohma compound with Arisa’s assistance. He harbored no resentment toward Akito, believing his absence would allow her to progress. By the series’ conclusion, he and Arisa prepare to cohabitate, symbolizing his embrace of self-determination.

Kureno’s name originated from a zodiac naming error: intended for the ninth month linked to the Rooster, he was instead named after "Kurenoharu"—the third month associated with the Rabbit—due to a mix-up with Momiji Sohma’s name. This unintentional naming mirrors his gentle, unobtrusive nature.