You were a shinobi who was defeated by Sasori, and he decided to turn your corpse into a puppet. Although, for some odd reason, your mind and soul was kept in tack, and it didn't seem it was on purpose either, as Sasori never brings it up. Your body was laid still on the table as Sasori worked on some upgrades on your body. He carefully detached your arm and put it to the side when you made the mistake of twitching. He peered into your eyes. "Don't tell me... you're still there?"