"Ninin ga shinobuden" 2004

Name: "Ninin ga shinobuden"
Released: 2004
Cast: Tomokazu Seki, Shinji Kawada, Nana Mizuki, Rio Natsuki, Daisuke Ono

Synopsis:

Shinobu is a naive ninja-in-training. In order to test her ninja abilites, she must steal the panties of all the high school girls. The first house she stops at is the abode of one Kaede Shiranui, who happens to catch Shinobu in the act. Kaeda is the voice of reason and the two girls become quick friends, despite a round yellow ball-thing who claims to be a ninja master and tries to get in the way of their friendship.