Don't get me wrong, I don't hate the new Fairy type or anything, I just don't think it makes sense for it to be strong against the Dragon type. Had it been Magic type or something, I could see that, but... :/
All silliness aside it was about time for a new type to be added, and about DAMN time we found out Sylveon's type.
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NamelessTraveler
At first I thought that it was a crazy move to make a new type (And call it Fairy at that) but looking at how many Pokemon are so cutsie and well.... Fairy-like, it fits. x3
As far as them being strong against Dragon, I dunno. I guess in most games I've played magic is always strong against dragons (Though like you said, they could have just as well called it Magic type), but with so many Pokes being fairy like, and fairies having magical powers, I guess that's what stuck. :3