She's not from an アニメ she's an original artwork によって Fluorocarbon on Pixiv, however it would appear they for some reason don't keep all their art work up, または I'm somehow missing it I don't know. I found the picture あなた 投稿されました on deviantart (the user uses the watermark in the picture あなた posted) and they claimed that the original picture (they only took out the background) was 投稿されました によって a person named fluorocarbon. I searched that name and I got many results of people posting other works によって this person, along with their pixiv, but on their pixiv I didn't see a lot of pictures people had reposted. I also looked the name up of zerochan (where the person who 投稿されました the pic あなた have on deviantart claimed to have found it) and I didn't find this exact image either, but under the same artist and with similar style. So I can assume for one reason または another they don't keep all of their art up, but I believe that to be the person who made the original of that image. Long story short there is no anime.
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