Doris Ruridou

As the third and smalles daughter of the rich family that owns Rasen Advertising her usual rich way of living gets spoiled by her being forced to go to a all girls boarding-school. Doris is also a Panzer and can at will transform into the Drill Princess. The name comes from her using a drill as both a weapon and a fashionable hat though no one else seems to think that her Panzer-suit is.