Prism is the nickname of the YWP user with the username VioletsAndPrisms. She has in her bio that she can also be called Kira or Violet (she had gone by Violet on other places online before knowing about the YWP user Violet), but no one really calls her anything but Prism.
She joined the YWP site sometime in October or November 2016, but was not active until October 2017.
She has not made many notable contributions to the site, but has created the briefly semi-popular thread "In Which We Ship Characters From Our Own Novels" and has a cover and moodboard shop in the Art Class forum. She has participated in all of the CAYCDs since October 30 2017 as various characters from her novel.
Prism coined the word Decembewrimo on December 1 2017 to describe the action of finishing one's NaNo novel in December and the people who do this. The forum thread about this has more than 100 posts.
According to her bio, her favorite novels/authors are "HP, WoF, The Lunar Chronicles, Rick Riordan, the Leviathan trilogy" and her non-noveling interests are "Reading, drawing, foruming, theatre, horseback riding."