King Slimes are my second favorite slime. Second only to... METAL KING SLIMES!!
In case you aren't too familiar with the characters from the Dragon Quest (ドラゴンクエスト) series, the girl on the grass is Barbara (バーバラ ), not Ashlynn, from Dragon Quest VI and in the King Slime hot air balloon is Alena (アリーナ) from Dragon Quest IV.