Based in Kobe, Japan, 19-year-old Yu Inagawa hails from a family running a traditional inn and hot-springs resort she is destined to inherit. This heritage earned her the distinctive nicknames "Hot springs Panda" or "Panda Onseniko," referencing both the family business and her characteristic large, round glasses resembling panda eye patches. Standing 155 cm tall with brown hair and brown eyes, her birthday is December 7.

Yu is an energetic, passionate doujinshi artist, the sole member of circle "Karamitei." She specializes in parody works—though she prefers "homage"—dedicating herself so intensely that she sometimes neglects studies or daily tasks like food shopping. She frequently hurtles from Kobe to Tokyo for Comic Party conventions.

She exhibits a lighthearted, caring personality marked by intense enthusiasm for her craft. Yu communicates rapidly in a distinctive Kansai dialect, described as talking like a waterfall. Her doujinshi philosophy prioritizes genuine customer satisfaction and respectful fan engagement over pure sales, often bringing her into conflict with the commercially driven Eimi Ohba. Yu reacts confrontationally to criticism of conventions or doujinshi culture, sometimes impulsively hitting detractors on the head with a large fan.

Her narrative role centers on mentoring protagonist Kazuki Sendō in the doujinshi scene, providing practical guidance on publishing, exhibition logistics, and industry conventions. She later becomes Kazuki’s classmate after relocating to Tokyo. Her development consistently shows her balancing inherited responsibilities with creative passion, committed to doujinshi only as long as it brings joy to herself and others.