Cassie

Cassie is a main character in the MattBoo universe, based on Stone's elementary school friend of the same name.

History
Introduced in Matthew's World on 2006, Cassie has faced many changes in personality. Originally, Cassie had the same personality as the person she was based on: a normal, well-behaved, and nice girl. But around 2007, Cassie started changing. Instead of a normal girl, Cassie became more of a tomboy, as well as disgust in girly stuff, gained huge strength, became adventurous, and gained superpowers. But around 2009, the superpowers were completley removed.

Matthew
Cassie is good friends with Matthew and likes to hang out with him. She even battles with Matthew, due to her adventurous personality.

Xsaviar
Cassie does not recommend Xsaviar as her friend. Xsaviar has a moronic personality, and Xsaviar is sometimes the cause of Cassie's problems. But sometimes, Xsaviar is good to hang out with Cassie, due to Xsaviar always being in battle.

MattBoo
Cassie has a few issues with MattBoo's "irritatingly cheerful attitide", but besides that, MattBoo and Cassie are good friends.

Levi
Cassie has a big hatred for Levi. Mostly, Cassie threatens to pummel Levi, or even kill Levi if really ticked off. But sometimes, Cassie might feel bad for Levi if she gets rid of him, so she doesn't entierly hate Levi. On, May 20, 2012, the reason why Cassie hates Levi was revealed on the MattBoo Productions Tumblr blog website. The reason was because Levi accidentaly broke Cassie's $1,000,000 charity check.

Callie
Callie is Cassie's best friend, but sometimes, Callie's girly nature kind of annoys Cassie.

The world around her
Callie seems to dislike the people in acquaintance with her. They annoy, irritate, upst, and anger Cassie, and, similar to her hatred of Levi, it was revealed on the MattBoo Productions Tumblr blog website on May 6, 2013 that the stuff they do drive her insane.