Martha

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http://sonnywithachance.wikia.com/wiki/Martha

Martha (Emma Hunton) is the bully who Grady believes is in love with him in the episode "High School Miserable".

"High School Miserable"
Martha only appears on the in a group dream sequence. When the cast of So Random! arrives at high school, she starts out by intimidating them by dragging Grady into the bathroom to give him a wedgie. When Grady finally returns to his fellow cast members, Sonny convinces him that Martha must like him. Grady for the rest of the dream sequence refers to Martha as his "girlfriend". Martha continues to harrass the cast (mostly Grady) for the rest of the episode. She does not appreciate theSo Random! cast's song and dance or Sonny Munroe's Apple Initiative. And though Martha does not care much for the ''So Random! cast, she appears to be in love with Chad and MacKenzie Falls'' and tells Chad to protect himself from the Randoms. Martha disappears after the dream sequence, but she is mentioned at the end of the episode when Grady stands up to find his underwear tied to his chair. She appears to be a bully.

Grady Mitchell
Grady believes, after Sonny's convincing, that Martha is picking on him because she likes him. He spends most of the episode thinking all the attention Martha is giving him is her sign of affection. Martha does not appear to share the same feelings for Grady. Though Grady and the rest of the cast wake up from their dream sequence, it appears that Grady does not have any affection towards Martha either.

Trivia

 * Martha teaches Grady about all thirty-six types of wedgies. Some of them include: the "Hoodie", the "Wedge of Allegiance", the "Monkey", the "Bowling Pin", the "360 Spin", the "Hourglass", the "Peg Leg", the "Bat", and the "Donkey".
 * Martha, together with the Principal and the other schoolmates, is only an imaginary character by the So Random! cast.