Himesama Goyoujin

Princess Beware (姫様ご用心, Hime-sama Goyōjin) is a 12 episode anime series, produced by Nomad, that aired on WOWOW from April 12 to July 19, 2006.

Plot
Himeko Tsubaki is a xenophobic schoolgirl in a tennis club who, thanks to a couple of bumbling foreign thieves, accidentally comes into the possession of a magic crown that turns her into a princess (much to the chagrin of the crown's true owner). Everything seems to come in Himeko's way as the crown magically fulfills her every wish, but it makes her a prime target for the various people who want the crown for themselves.