Doubles is a character who only appears in the episode The Trouble With Bubbles.
Since she was a clone of Bubbles, her personality would be the exact same as her. Although, she was accused of acting a bit suspicious in the episode she was in, as she was acting weirdly by saying she was back from apple picking. When previously, she claimed she was going to help the Mayor fix his car, but the clone claimed his car broke down next to the Apple Orchard, giving a chance to go apple picking. The next supposedly suspicious act claimed by Buttercup was on how she completed her to-do list, relating to the Alien thing on the TV that Blossom and Buttercup were watching.