A dying mob boss entrusts Lupin with a diamond that supposedly is the key to a vast treasure. But when Lupin is attacked by an assassin and saves a mysterious girl from trouble, it becomes clear that that there's more to this treasure then meets the eye... 

(Source: ANN)

Episode 26 included in the ninth DVD volume of Kaibutsu Oujo.

When Saga—now 15 years old—arrives at her home after a day of errands, her grandmother Regina discovers an old dress in the attic. At this point, Saga recalls the time her elementary class participated in a play titled "Princess and Fairy." She volunteered to play the role of the Princess while her rival Greta played the evil witch. The production of the school play reminded Sugar and the other fairies of the time "The Bear Pianist" played in the town not too long ago.

This special follows the story of how Isaki Shuuji and Ruo Minai became Contracted Priest and Shikabane Hime.