Arale-chan to Yukai na Kaizoku Ikka

Arale, Obotchaman, and Gatchan are hired by Prince Arscher, who wants to rescue his fiancée, Princess Pitchipitchi, after she has been kidnapped by pirates. However, Pitchipitchi faked the kidnapping herself to find out if it is true that Arscher is a stingy coward.