Who is Karla from Microserfs and what is their importance?

Karla is a young, neurotic and extremely intelligent young woman who works in an office close to Daniel's at the Microsoft Redmond headquarters. She warms up to him after he brings her food and origami paper. Little by little, she reveals herself to Daniel until she becomes fully in love with him. More secure with herself, she lets her hair grow long and becomes more attractive. This attracts the attentions of other men, which she finds uncomfortable and disturbing.