Kanzen na Otona (完全な大人) is a solo b-side sung by Ono Sayuki, featured on Morning Musume's 54th single, Wagamama Ki no Mama Ai no Joke/Ai no Gundan. It was featured on the Limited Edition A and Limited Edition B of the single.
Kanzen na Otona: 1
Tsunku's comment on the song
Kazen na Otona was originally meant to be for Saburo Mami, but I decided that Ono would be able to handle the song more. The song has a lot of pitch changes and has severely high notes, the perfect song to show off Ono's vocal capability. The song also about a young girl who wants to become the perfect adult, something Ono wants to be. This song should be able to snatch the heart of fans.
- This makes Ono Sayuki the first tenth generation member to get a solo song.
- This is the only solo b side featured on Wagamama Ki no Mama Ai no Joke/Ai no Gundan.