Wikipedia
Prizmmy☆ (pronounced Purizumī in Japanese) (Prizmmy☆ = abbreviation of the words "Prism With Me" ) is a Japanese girl group under the management of Avex Pictures.
Prizmmy☆ was previously a trio, consisting of Mia Kusakabe, Reina Kubo and Karin Takahashi, called Prism☆Mates. Later joined by Ayami Sema who got in by winning Kiratto☆Entertainment Challenge Contest 2011 SUMMER Pretty Rhythm Award. In 2012, they debuted as "Prizmmy☆" with debut song "Everybody's Gonna Be Happy" which is also the 4th ending theme song for anime series Pretty Rhythm: Aurora Dream.
They are well known for singing most of the theme songs for Pretty Rhythm: Aurora Dream, Pretty Rhythm: Dear My Future, Pretty Rhythm: Rainbow Live and PriPara anime television series. In Pretty Rhythm: Dear My Future the main characters of the anime are illustrated after the original members of Prizmmy☆.
Prizmmy☆ has a sister group called Prism☆Mates who also accompanied them in hosting "Pretty Rhythm Studio" in Pretty Rhythm: Dear My Future and Pretty Rhythm: Rainbow Live anime series. Prism☆Mates' members include of : Mirei, Yuka, Momona, Airi and Sana. (Previous/Graduated members : Hina, Runa, Kanon, Natsu.) Prizmmy☆ and Prism☆Mates together make another unit called "Prism☆Box"
On 30 March 2014 Ayami graduated from Prizmmy☆ and it was later announced on 5 April 2014, that Prism☆Mates' member Hina will continue activities as a member of Prizmmy☆ replacing Ayami and thus graduating from Prism☆Mates.
On 2 May 2015, Prism☆Mates' member Runa graduated leaving the group.
Later, a sub unit of Prism☆Mates named "プリズム☆アイドル研究生" ( Pronounced = Purizumu☆aidoru kenkyūsei, meaning = Prism☆Idol Research Student ) consisting of members Airi, Momona, Mirei and Yuka debuted with the song "アイドルキンリョク Lesson GO！" (Idol Kinryoku Lesson GO!) which is also an ending theme song for PriPara anime television series.