Shina Kamijo displays a strikingly youthful appearance, often seeming half the age of her husband Kamijou Touya despite their comparable years, a point noted by others including their son Kamijou Touma. She embodies elegance through ladylike conduct and polite, indirect speech punctuated by her signature "Ara, ara" interjection. Her wardrobe consistently features ankle-length white dresses, cardigans, and a white brimmed hat, accentuating her "Ojou-sama" aura.

Her personality merges poised grace with simmering intensity. While typically calm, she reacts fiercely to protect family bonds, particularly directing jealous glares at women near Touya. She engages in reciprocal flirtation with him, even allowing him to choose provocative swimwear for her. Paragliding forms her core hobby; she trains rigorously through swimming to enhance lung capacity. Neighborhood residents recognize her for frequently sending Touma aerial home photographs mid-flight.

Devotion defines Shina’s family life. She primarily stays home while Touya travels internationally for work, accumulating souvenirs that crowd their residence. During Academy City visits like the Daihasei Festival, she trusts Touma’s judgment when he disappears mid-competition and waits at the hospital after his injuries. Learning of his involvement in global conflicts, she contacts Academy City for updates and humorously considers throwing objects upon his return—a reaction mirrored toward Touya.

Her narrative involvement starts with the Angel Fall Arc, where a spell swaps her appearance with Index. Mistaken for Index by Touma, she becomes ensnared in events and is drugged by Tsuchimikado Motoharu to prevent interference. Later, her paragliding photos help Touma locate a home intruder. At the Daihasei Festival, she befriends Misaka Misuzu while exhibiting jealousy toward women approaching Touya.

During the Homecoming Arc, she discusses family concerns with Misuzu at a fitness club pool, revealing awareness of Touma’s presence in Russia via news reports. Her frustrating attempts to extract his whereabouts from Academy City yield no results.

In the Magic God Othinus Arc, she displays resilience when trapped with Misuzu during Gremlin’s Tokyo assault. Her voice message on disaster boards reaches Touma during his fight with Freyja, spurring him to seek rescue allies. In Othinus’s alternate world branding Touma an enemy, Shina and Touya face trial as his parents. They publicly disown him to appease authorities, pledging to "correct their mistake," intensifying his despair.

Recent activities include sending Touma New Year’s postcards and minor participation in the Resurrection Arc. As Touma’s mother, she and Touya permitted his Academy City transfer despite his misfortune, though her specific influence on this decision remains undefined. Daily life centers on household management and hobby-related updates to Touma. Her friendship with Misuzu evolves through shared sports facility visits and mutual concern for their children.