Big Duel, Zorori Castle

Zorori must battle against five rouges to free a princess and win her castle. He gets magical shrinking and growing medicine to help him, and in the end the castle is destroyed when Ishishi and Noshishi grow to enormous proportions. The rescued princess has been cursed to sleep as a frog. Zorori kisses her but storms away when nothing happens. A minute later the princess returns to normal and awakens. Based on book 20.