There are three primary statistics in Pokémon-Amie, viewable when you select a Pokémon to play with from the Pokémon-Amie app.
Note : This stat is completely independent of the Pokémon’s Happiness stat (the one used to calculate Return/Frustration’s damage and determine when certain Pokémon evolve)!
By far the most important, this can help to determine the battle effects you get, detailed at the end of the previous section. It is raised by petting Pokémon, playing Make Faces with them, playing minigames, and feeding Pokémon PokéPuffs. It maxes at five hearts.
Specifically, Affection is denoted by how many hearts a Pokémon has given off when you’ve done various activities with it.
|Affection||Hearts Given Off|
This determines how many PokéPuffs your Pokémon can eat; there’s a general "1 PokéPuff, 1 unit" correspondence here. If the Pokémon begins to eat slower or even just ignore the food, then the Pokémon is getting fuller.
In other words, it’s a long and tedious process to raise Affection by just eating - the quickest way to a Pokémon’s heart is not through it’s stomach. Anyway, this is lowered by playing minigames.
Simply put, it denotes how often you play minigames; the more music notes, the more you’ve played minigames with it recently. It also increases as battles are done in the field involving the Pokémon in question.