Yuu Tokonatsu

Yuu Tokonatsu (常夏 夕 Tokonatsu Yuu), Terumi's seventh sex conquest, is a dazzling, 22-year old who works as an instructor at the Shiun University Club. She plays the role as Yuuago from Tales of Genji

Background
She used to be a sickly girl growing up, but eventually became as strong as any regular sportswoman some point at the age of 19. She first met Kaoruko when she was in middle school while visiting the university.

Plot
She first met Terumi during one of her jogging lessons and was later officially introduced after she was invited to Kaoruko's home. Terumi signed up for her lessons at Kaoruko's suggestion, but accidentally caught Yuu cooling herself half exposed in a private room. This made their interaction awkward for a while until one day she helped Terumi after he collapsed by the treadmill due to over exhausting himself(from running from his desires of Kaoruko). As she interacted with Terumi more, she found herself feeling complicated by her own desire relating to find love and interested in Terumi. Through Kaoruko's advice and suggestion, Yuu and Terumi went on a few dates as pretend couple. They became a real couple after visiting the batting cage, the same night, they had sex for the first time at a nearby motel. Unbeknown to them, Rokujo was next door spying on them. At first, Yuu was concerned if Terumi still lust after Kaoruko, which he denies as he want to devote his heart to her alone. She eventually came to trust him more, enough to support Terumi's crossdressing to defeat his bully in a Beauty Pageant, despite her preference of masculine man.

The day after the pageant, she went on a business trip to Osaka, where the headquarter of the fitness center she work for is located. She accepted a job offer to work in the headquarter, as the opportunity was too good to pass up.

Trivia

 * She's the first girl introduced in the series to have an accent, as well as being an athletic type.