Well, I can't really say something negative to it. And maybe I'm repeating myself, but in my eyes, this Pokémon's Design and idea is by far the best in Gen VII (alongside Cutiefly).
Thus far, all we know is that trying to remove the Pikachu disguise--which it uses both to protect itself from sunlight and to try to curry favor with humans--gets you hit with an illness.
I was kind of hoping that the first Ghost/Fairy pokemon would be a banshee, though. {sulk} (Or maybe this critter can learn Hyper Voice and/or Perish Song...?)
I wonder what kind of f*cked up shit they will put in the pokedex entry of this pokemon.
I'd be tempted to guess something along the lines of Duskull or Drifloon; using the Pikachu-facade to lure people astray and all that.
As an aside, that it's Fairy-type brings to mind that yes, there's plenty of nastier creatures lurking under that banner, including some that are frequently considered undead, so I do wonder if any of them might be referenced by its abilities and 'dex entry.
EDIT: So the Pikachu disguise is removable, eh? I do like that there's stated reasons for it being used in the first place, though.
Guys, it's not like that - from infos we know from pokemon site, this little critter use remains of pikachu merchandise that was popular 20 years ago on Alola because he want to be loved like Pikachu. It's just lonely.