She was under pressure trying to bake enough cakes for the celebrations, so she infused Dark Matter into the batch, creating the Carnivorous Creep Cakes, due to the dark powers and chaos that is contained with in Dark Matter. In the “Total Caketastrophe”! prestige mission, her kitchen has been infested with the Cake Creeps and needs assistance, so the player and their party are assigned to help.

Apparently, she is very embarrassed by the events, so she tries to cover up the whole incident.
- Spiral Knights Wiki
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For some reason, I tend to like barely known NPC more, than more active ones. That, and her design is just perfect, I really love the robot-knight-chef combination, Biscotti is just beyond adorable to me :>
Sadly, I got into game when Caketastrophe event was over, but maybe I’ll be able to join it next time.