I'm not all that surprised by Rainbow's response. From her point of view, Fluttershy just snogged her out of nowhere and then professed her love to her. I think that would catch anyone off guard, even the fastest pony in Equestria.



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I love the composition in this page. It's really just their two (marvelously well drawn) heads, but the addition of the frames just adds something. We can focus on each one separately, but they still come together as one single image. But at the same time, there's the symbolism of that schism between the two characters and how so little of them, for the moment, seems to be part of a whole.