“Yumi’s Cells” — the webtoon that turned one office worker’s love life into a cast of cartoon brain cells — opens as a stage musical on June 30, 2026, running through August 23 at the CJ Towol Theater in Seoul’s Arts Center, according to a post from Tiffany Young’s official project account and reporting from Anime News Network. It’s the property’s first-ever stage adaptation.
Girls’ Generation’s Tiffany Young and actress Kim Ye-won are splitting the lead role of Yumi in a double cast, alternating performances. That alone would be enough to get K-pop fans into seats who’ve never read a single panel. But the more interesting swing is on the cell side: the musical is introducing a brand-new character, a mysterious cell called “109,” played by Jung Tae-woon (VIXX’s Leo) and Jung Jin-woon — and 109 doesn’t exist anywhere in Dong-geon Lee’s original webtoon, per Anime News Network’s reporting.
That’s a real risk for an adaptation. “Yumi’s Cells” built its entire fanbase on a very specific gimmick — narrating an ordinary woman’s daily life and relationships through the personified cells running her brain — and the cell cast is basically the IP’s signature. Inventing a wholly new one for the stage version means the production is betting it can expand the universe rather than just restage it. The production is being staged by SEM Company alongside Studio N, Naver Webtoon’s in-house adaptation studio, which has every incentive to make sure new characters feel additive rather than gimmicky.
If you’ve only seen the 2021 TV drama version starring Kim Go-eun, this is a genuinely different animal — a stage show built around the cell characters that the live-action adaptation mostly downplayed. Tickets are on sale now for the run through August 23.
Sources: Tiffany Young Projects (@TiffanyProjects), official update, June 2026; Anime News Network, “Yumi’s Cells Webtoon to Receive 1st Stage Musical Adaptation,” April 3, 2026.
