Draco in Leather Pants: Holy SHIT, Leon. While he does have somewhat understandable reasons to be the way he is, these do NOT justify how his fangirls handwave or ommit the crap he has pulled on Sora, May and on many others like the innocent partners that he injured just to test their worth.
There's a quite sizable chunk of subtext between several girls of the cast. Sora and Layla, Sora and Rosetta (which crosses the line to Pseudo-Romantic Friendship in the second season), Sora and May, May and Rosetta, Anna and Mia, Mia and Cathy, Cathy and Layla...
Arguably, Cathy with Layla and Mia. So much that Sora even gets a little jealous of her closeness to Layla at some point!
Misaimed Fandom: Some fans are so protective of Sora that they peg Kalos, Leon and especially May as evil. Often while whining about how Sora should be spoonfed and showered with love and praise - which is funny because, had Sora gotten approval and love easier, the fandom would've doubtlessly whined about her being boring and perfect.
Unintentionally Unsympathetic: Sure, Leon has a pretty terrible Dark and Troubled Past. But to many fans this does NOT excuse him intentionally injuring several of his partners (including May) and possibly ruining someone's career out of what is essentially spite. It doesn't help that he's not really called out for this and that Sora was just expected to trust him as a partner.
Wangst: Sora's problems in the second season are very valid, but sometimes her angst does get extremely grating. Lampshaded by Fool, who tells her that if she doesn't come around, she'll lose her chance to be the Kaleido Star, and as such she'll stop seeing him. And it happens for a while.
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