Complex sentence: While attending Metropolitan Musashigaoka high school, she formed punk rock band "Mari band", and after being admitted to Aoyama Gakuin University, she worked as a vocalist in "Misty Cats".
Split into simpler sentences: While attending Metropolitan Musashigaoka high school, she formed the punk rock band "Mari Band". After being admitted to Aoyama Gakuin University, she worked as a vocalist in "Misty Cats".