Otsuki Riko

 (大槻りこ) is a Japanese idol and a member of Eisei To Karatea and a former member of PiiiiiiiN.

She joined PiiiiiiiN in August 2019, and graduated on August 8, 2020, where the group disbanded.

She was revealed as a member of Eisei To Karatea on June 23, 2021, tho all joined on June 17, 2021.