Question: how to evolve eevee into sylveon in omega ruby?
Answer: To evolve Eevee into Sylveon, you have to raise Eevee's affection to at least 2 hearts in Pokemon Refresh (SMUSUM), the PlayNav of the PokeNav Plus (ORAS) or Pokemon-Amie (XY). You get Pokemon Refresh and Pokemon-Amie at the beginning of the game, but they become usable after you get your first Pokemon.