Is there any reason to play with the overworld Pokemon?
In Pokemon Ultra Sun and Moon, there are various overworld Pokemon you can interact with, where you and it get to play. Some examples of the actions are spinning to the left, right, and playing peekaboo. Is there anything hidden in this, or is it just a cute little distraction?
Solution 1:
According to Serebii, interacting with the overworld Pokémon will increase their affection towards you. A higher affection rating means they will come up to you more often.
Aside from that, there is no other benefit in interacting with these Pokémon.