Candy Apple Dentistry is the third stage in Summer Diary.
A Squire Rel will be spawned in the beginning. Shortly after, the boss Drummer Doge will be spawned along with Croco, B.B.Bunny, Squire Rel. All cat units will be frozen for 1-2 seconds and regularly thereafter. Shy Boy and Mooth will then spawn.
This stage isn't difficult to beat either despite the appearance of Shy Boy. Rushing the stage with Cow Cat will do the trick. Your cats being frozen by the boss might be a little annoying though.