Sarah

Sarah also known as "Sarah the Dude" is one of the two main antagonists in Tennis. She has very short hair like Anna.

In Tennis
Sarah was a very popular girl until two bullies arrived and shunned her out. She remained traumatized for the rest of her life and became villainous and is Elisa's sidekick. She got used to helping her torture and manipulate people. She got arrested along with Elisa at the end for torture and manipulation.