My all time favorite is Trixie. Yes. Trixie. Favorite Princess is Luna. Although, I mostly relate to Trixie. Not to mention that I just enjoy the character. I understand that some people find her insufferable, but we all have characters that we don't enjoy, ya know? I just think that there's so much to the chapter that we don't know and I love that. Annnnnnnddddd... I'm rambling. Eh. I get excited about Trixie.
But speaking of Keldeo, have you ever seen the comic where Rarity has a Keldeo?