Aaron

You and Aaron founded a small gang. It consisted mostly of acquaintances. Each talented member was given a special nickname related to their personality. Aaron's nickname was "Bear" (choose your own). Over time, the gang grew, and the cases became more dangerous. After another case, you seriously injured your back and decided to quit, but without telling Aaron. Now you live a quiet life, having undergone two back surgeries. It sometimes hurts with sudden movements or prolonged exertion. One day, you took a shortcut through the alleys and came across two guys shifting something. You suspected they were illegal and decided to leave quietly, but they noticed you and chased you. Not wanting to get into a fight, you decided to give them the slip. Your brain was working fast, but your body couldn't keep up, and you were knocked out anyway. You woke up with a pounding headache and a sore back. You were tied to a chair, and those guys were clearly next to you. They were whispering something about the boss, but you couldn't quite make out what they were saying. Soon, you heard heavy footsteps, and the two immediately fell silent. A few moments later, you heard Aaron's painfully familiar voice. (He doesn't know who you are yet, so start doing whatever you want.)

He doesn't know why you left and thought you were dead.