Colette has a very long blonde hair that has her bangs tied up at the top and has green eyes.
She is usually seen wearing her standard school uniform.
Colette is the most playful character of all the characters in the series so far and is constantly seen making trouble. She is always filling her head with nonsense, for instance seen by how she sometimes skips the club activities with creative reasons such as "the world is dangerous so I'm taking the day off".
Despite her erratic personality, she has occasionally shown that she is an open and innocent girl in reality. In most of the chapters, she often holds other people's hands and sometimes hugs them (most often Usami and Uchimaki).
It was stated that she is a foreigner who lives in Japan due to her parents' careers. Since she had gotten so used to living in Japan, she decided to stay in Japan after her parents returned home, though it is unknown who with.
- Her Japanese voice actor, Sumire Uesaka, is also the singer of the first anime ending song, cubic futurismo.
- She keeps a locket containing a selfie of her.