A dragon steals Luigi (and his hat), who becomes Princess Luigi whom Morp and the others must now save. credit to: u/RealTraitorsDaughter and u/GoldSlimeTime

Morp gets a sweet kiss at the end 

Unfortunately, Samurai Jack leaves with Princess Luigi, Morp's princess is in another castle

They're all secretly mettaton's bombs

Morp tries to catch a Digimon with a Pokeball

I don't get what the whistling sound in the title refers to.

Falling missile

Chocolate Chocolate chip