
Quick answer — Kaya Okuno voices Yaya Sasame in HaNaYaMaTa, Kaya Kikuma in Wake Up, Girls!, Hacka Doll 2-gou in Hackadoll the Animation and 6 more characters.
Kaya Okuno voices Yaya Sasame (HaNaYaMaTa), Kaya Kikuma (Wake Up, Girls!), Hacka Doll 2-gou (Hackadoll the Animation), Tama (Death March to the Parallel World Rhapsody), Filimøs Harrifenas (So I'm a Spider, So What?), Horiguchi (Mieruko-chan), Petra Hubarek (Sweet Reincarnation), Karen Kisaragi (Hundred) and 1 more.
Yaya Sasame is voiced in Japanese by Kaya Okuno.