Funnily enough a Fluffdragon's usual favorite instrument of choice are Brass Horns of some kind. In this case, Dogry is using a trumpet. Instruments can sometimes add more Rapport bonuses to the people of the Shattered Islands.
In many cases Fluffdragon Civilians in the world of the shattered islands will cheer on other people during their tasks, among other things.
This is usually pretty helpful, unless the person receiving their cheers is a bit sensitive to noise. Then they might not be able to think straight. Getting a trumpet blown at you from behind would be quite startling.

Rapport actions are inspired by the TTRPG system Fate, as well as maybe Ironclaw. I like the idea that some characters can use their action to help others excel or recover from bad effects.