Moonflower is an Alchemist, and asocial recluse, Just like Amaryllis. Living alone in a Unicornia Apartments and focusing only on her studies.

She was very jealousy of Amaryllis intelligent.

When She's was a filly. Moonflower thought She catches Amaryllis talking math with her bird friends, And openly accuses her of cheating on the test

Amaryllis explains that she was just settling an argument about bird nests, but Moonflower doesn't believe her.
She goes up to the chalkboard and solves a complex math equation without the help of her bird friends, So much to Moonflower's embarrassment

Moonflower became heartbroken and withdrawn, After Amaryllis didn't showing up to the birthday party.
Amaryllis was her only friend...