Ok so it took me a while to find it but this is Kirin's current hairstyle from the date in .30 update:
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and a non-cannon image
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Her hair doesn't quite fit the silhouette
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So its probs Ami w/ a slight head turn to obscure 2nd pigtail.
On that note of Chika being @ Maid Café, hope we get more of this with Uta-Chan!
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Disappointed that Uta-Chan was not a choice option for Chika 3some offer (but Can't remember if the chin scratch happens b4 or after ask)