Buffy

Muffy let out a little gasp. This girl had on a bracelet she had admired at the jewelry store. But her parents had said it was too expensive, even for them. Buffy is a student of Glenbrook Academy in Mr. Pryce-Jones' 3rd grade class, and the doppelganger of Muffy Crosswire. Her first and only appearance so far was in "The Return of the King".

She went against Muffy in the tennis match, but Muffy's modern racket broke before they could play the 16th century version.

Buffy used a 16th-century tennis racket that (supposedly) was passed down from Henry V (her great-great-great-great-great-great uncle).

Physical appearance
Buffy is a rabbit with a cream complexion and hair identical to Muffy's, but with white bows.

She wears the Glenbrook uniform with a white collar shirt, a dark blue tie, a plaid skirt, a light blue V-neck shirt, and a medium blue jacket bearing the Glenbrook insignia.

Trivia

 * She may be making up the relation to Henry V, referencing "Background Blues".
 * She and several other Glenbrook students made a cameo appearance in the Library Card song of "Arthur's Almost Live Not Real Music Festival".
 * She is unnamed in the show, but the chapter book based on the episode says her name is Buffy.