Mona Vanderwaal is a main character from The Shadow Diaries.
- She used to be a major loser, and way back was tortured by CeCe Drake.
- But then once, she was in a tent, sleeping and it set on fire. CeCe and The Liars saw it, and CeCe ran to help. She took Mona out of the fire, and Mona was screaming. She saw that CeCe saved her, and she shyly said.."..Uh...thanks CeCe". Somehow since then CeCe invited Mona to hang out with The Liars, and she eventually became part of the group.
- She was revealed to be a member of the "C" team.
- She was mostly best friends with Clara. They always hung out together.