Quick answer — Yuiko Ōhara performed 5 anime themes, including "Iwanai kedo ne." from Teasing Master Takagi-san, "Ketsui no Uta" from Mushoku Tensei: Jobless Reincarnation Season 3, "Kirameku Hamabe" from Land of the Lustrous.
Yuiko Ōhara performed the anime theme songs "Iwanai kedo ne." (Teasing Master Takagi-san), "Ketsui no Uta" (Mushoku Tensei: Jobless Reincarnation Season 3), "Kirameku Hamabe" (Land of the Lustrous), "Mamoritai Mono" (Mushoku Tensei: Jobless Reincarnation Season 2 Part 2), "Musubime" (Mushoku Tensei: Jobless Reincarnation Season 2).
Yuiko Ōhara's first listed anime theme is "Iwanai kedo ne.", the opening of Teasing Master Takagi-san.
