Here are the Rock Band in-game avatar characters that the main characters created. They describe a little more about each character's personality...
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And here are Ji's angry Korean parents:
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and her annoying little brother who also happens to be a super genius:
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AND MOST EXCITING OF ALL, THE RIVAL BAND!!! They are jerks sort of.
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Left to right they are the ranked Korean Starcraft player, the Rebel girl (who Ji not-so-secretly wants to be), the pushover GameStop worker, and the douchebag guy who plays his guitar in the cafeteria and has a gig playing bad RHCP covers at the local coffee shop.
OH MY!