Utsugi Rio

 (宇津木りお) is a Japanese idol, founding member of Niconico♡STAGE and former member of Princess wa Nemuranai! and 3-ji no Oyatsu as Ichikawa Rio (市川りお or 市川里緒).

She was a founding member of 3-ji no Oyatsu and graduated in June 2019.

She then joined Princess wa Nemuranai! in November 2019 and graduated on September 8, 2020.