(sorry if bad english or something) Enstars is the short name that stands from Ensemble Stars. Enstars is a game, well, actually the game was Ensemble Stars! but this year they change it to Ensmeble Stars!! Basic, Ensemble Stars!! Music, Ensemble Stars!! Only Your Stars version (OYS) and I think another one and the chinese version of the Basic and the Music. It was realised in 2015, so this year they celebrate its 5th aniversary :D. Enstars has also an anime, relised in 2019, it has 23 episodes. There are some facts that I just check yesterday because yes.
Leo Tsukinaga's younger sister is Ruka Tsukinaga, she's a character from Ensemble Girls.
Mika Kagehira has a probably lost twin called Suzu Kuromori, also from Ensemble Girls. Mao Isara has a design that looks like the same as Mai Anjo, from Ensemble Girls. I don't know if this helps a lot, but it's a great anime and the game is good too! Btw, the diference between the Basic and the Music is that the Basic (the one I have) it's like the old EnStars game, but just with new art and more developed. And the Music one, it's a rythym game, I don't have it and it's kindda dificult to download it for me.
If you get into the fandom, I'm sure you'll don't regret, and if you like it, we can talk by private :)
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