D4 Princess

is a 1999 Japanese anime series, directed by Yasunori Ide and produced by Studio Duame. It aired for 24 episodes between April 6, 1999 and September 28, 1999.

A light novel adaptation of the series written by Ryuji Arai, with illustrations by the original creator, Shotarou Harada. The series began publication on October 10, 1999 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
Doris Ruridou is young princess who had just entered Teito Academy. She is also a Panzer, a person with special abilities and fights with a weapon called a "tool". Shortly after entering, her older sister shows up to teach her how to fight as a Panzer against other Panzers who challenge her.