Talk:Star☆Twinkle Pretty Cure: Hoshi no Uta ni Omoi wo Komete/@comment-32714211-20190713215648/@comment-36644968-20190719173704

Because they are a pairs and both of them the true main protagonist from 5 Cures in this series.

Based my opinion, Star and Milky similar with Miracle and Magical, Melody and Rhythm, or Aine and Mio(Aikatsu Friends!). Even in each series has another main character but the true protagonist is always in that pair.

If you see Star and Milky Stocking, they only wear half pair which Hikaru wear in right and Milky in left. Another cure wear full pair.

Star Color Pendant(look At middle chest when they transform) has 2 shape Heart and Star.

Both of them has unique catchphrases. Cosmo catchphrase can't be unique because ~nyaa is always be used in Cat characters.