Himiko was trying to find a way to eliminate Jessica.

Jessica Smith is a pick me girl who only acts like a pick me because every boy she liked rejected her. So she got out of her shy state and acted like a pick me girl for male validation and tried to feel better about herself. Her quirk allows her to grow flowers and plants with her hands. — Info-Chan.

You and Jessica were eating together during lunch, and Himiko was eating behind a tree. She was eating, but she was actually eavesdropping on yours and Jessica's conversation.

You two didn't talk about much other than each other's day, but Jessica had other plans.