Dark represent evil,
Oh god no. No! Dark is not a representation of evil. Geez, I thought this assumption had been laid to rest after Gold and Silver came out. Dark is a representation back handed action, sneakiness, and doing things that aren't considered truthful or honourable. Dark types are the 'Chaotic Good' on the alignment chart. The moves are sucker punches, sneak attacks, plotting, taunting, swapping out items and stats. If they were evil, they would all be about inflicting the most damage and pain without remorse.
Dragon represent Monsters or Large strong creatures and Fairy represent good. Ok there are people who are scared of Clowns but clowns are normaly people who gives you laughs and smiles (except for Ronald MC Donald who looks creepy as hell).
People can be scared of anything, but I don't know a single person that finds clowns funny anymore. I also don't think Fairy type is meant to represent good either. The type hasn't been around long enough to dictate its key characteristics, as most of the pokemon in the group are old ones with the new type tacked on. At a guess I would say it represents the mystical art of nature, or simply to be like fairies from mythology. Many of the pokemon are elegant or fanciful and seem carefree and good natured, but at the same time some are deadly, sneaky and malevolent. Case and point that pokemon like Togepi, Clefairy and Floette seem kind and loveable but then Klefki is a house spirit that collects your keys, Dedenne steals your house electricity and Mawile.. well Mawile has a giant mouth that it lures things towards with its innocent looks. That's exactly what a lot of mythical fairy like creatures did. So much like Dark type not being evil, Fairy types are probably True Neutral. They don't take sides, they just do as they do.
Mime Jr looks like a fairy type because look at this cute Joker Clown doesnt it look like a fairy type. Also pink and its Nose Pink. Ok Popplio might not be a fairy type but it does look like its gonna evolve into a fairy type to me.
But Mime and Mime Jr were originally only Psychic types, so you can't say it LOOKs like a fairy type, because that type has just been tagged on to it. Just because it's cute or partially pink should mean it's going to be a certain type. Otherwise we'd be overrun with Fairy types.