When a player set a Pikachu as a buddy, it stays by an avatar's foot. By walking 10 or more distance, a player can get Pikachu sheet on shoulder.
Some small size Pokemon can sit on an avatar's shoulder. Unlike Pikachu, they can be on a player's should just be set as a buddy.
Large Pokemon, such as Snorlax cannot be on shoulder.
Best Pokemon to beat Snorlax
Best Pokemon to beat Dragonite
Best Pokemon to beat Muk
Best Pokemon to fight against Venusaur
What is DPS and EPS in Pokemon Go?
Best Pokemon to beat Magneton