OVA
Description
Aya Arisugawa, Kaname Arisugawa's older sister, lives with her family at the Arisugawa Bathhouse frequented by Nasa Yuzaki. She appears cheerful and gentle, with long periwinkle hair, purple eyes, and a preference for comfortable clothing or a school uniform. Tsukasa Yuzaki finds her pretty, and she enjoyed popularity in middle school.

Her airheaded, ditzy nature leads to frequent misunderstandings and quick confusion. Yet Kaname recognizes a "genius side," citing Aya's strong learning capacity, especially evident in her impressive video game skills. Gaming is her primary hobby, often convincing Kaname to join her. She streams online as "Ayapi," gaining renown for her expertise. She masters new games rapidly, matching experts like Tsukasa. Aya also displays notable resilience in saunas, self-trained as a "heat wave master."

Her family faced hardship when her father left her mother for a younger woman. Aya developed feelings for Nasa Yuzaki in middle school after seeing him easily solve a difficult math problem others struggled with. She harbored this unrequited crush for years without confessing. Discovering Nasa’s marriage to Tsukasa—initially mistaking Tsukasa for his sister due to their shared surname—Aya reacted with shock and distress when her mother publicly revealed both Nasa’s marriage and Aya’s feelings. Despite her heartbreak, she chose not to dwell, instead congratulating the couple to preserve the meaning of her first love.

Aya initially doubted Tsukasa’s suitability as Nasa’s wife. At a takoyaki party hosted by Nasa, she tested Tsukasa, leading to a video game challenge. Aya dominated Tsukasa in "Street Fighter V," winning twenty consecutive matches, but Tsukasa prevailed when they switched games. Their extended competition ended exhausted in a mutual draw at 1:00 AM. This fostered mutual respect, and Aya became a supportive friend to Tsukasa, affectionately calling her "Tsukachan."

She occasionally acts on whims inspired by television, like impulsively requesting help to build a backyard pond only to decide immediately after completion to drain it. Her relationship with Nasa’s cousin, Ginga Onimaru, is contentious, often marked by bickering. Her LINE messenger avatar features Rei Furuya. She identifies as a "game Otaku" and once remarked her first love ended "in a mere ten pages." Her mother dismissed Aya’s romantic disappointment as minor compared to her own experiences.