Usa-chan (real name Shiina Usami) is a 2nd year student at Ohananomitsu High School and Rentarou's 28th girlfriend. She's best known for being cheerful and energetic, though she has a pretty significant quirk: severe autophobia. She genuinely can't stand being alone, which means she won't do anything by herself—eating lunch solo, using the bathroom alone, you name it. If she ends up isolated, she'll panic and bolt away in tears, rabbit-style.
Her nickname comes naturally from the pun built into her name. "Usami" can mean roof, aid, and beauty, but it's also short for "usagi no mimi" (bunny ears). "Shiina" references castanopsis and apple trees. Put together, the whole thing sounds like "ugh, I'm so lonely" in Japanese—which is basically her entire character. Fans often note how fitting the name joke is, since her whole personality revolves around avoiding that exact feeling.
She tends to blend into crowds despite her outgoing nature, seemingly most comfortable when surrounded by other people.
Content compiled by AnimeList.moe from publicly available sources.
