Muffy Crosswire

Muffy Crosswire is a character from the PBS animated series Arthur.

Muffy Goes Metropolitan
In this episode, Muffy loses her left shoe while walking into a Subway Station and she hops around for a little while wearing one shoe.

A video of the action can be seen here: https://www.youtube.com/watch?v=LHWyz_ZWObw&t=9m35s.