A heavy-set girl with brown hair which she wore in a bob, Serena dressed in a pink shirt with a pale collar and short dungarees. She was a greedy pig who ate chocolate any time she could. She also treated her younger sister Ellie very badly.
One day, Serena caught Ellie breaking a flyswatter and blackmailed the girl into being her slave. However, Serena ate a piece of chocolate which had a fly egg inside. This made the girl turn into a fly herself, and Eli swatted her, finally freeing herself from her bullying sister.