Sisterhooves Social was the first MLP episode I watched that had Rarity as part of the main focus.  And it also happens to show her overcoming one of her greatest weaknesses.  Before this point, we hadn't been given much focus on the relationship between Rarity and Sweetie Belle.  But even with just a couple of minutes of screentime during Stare Master, we get a pretty good sense of what Rarity thinks of Sweetie Belle.  And vice versa.

DRWolf Narrator by DavionX:
http://davionx.deviantart.com/art/DrWolf-Narrator-377863090

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