@Sarangpata Follow-up response to forum #132904
I'm most definitely certain that haijin does not have a twitter or tumblr where you would have found that, and if he does, it is not documented anywhere online. Wherever you found it must have been a repost or a third-party website, but we'll never know since it's unsourced.
Can't be a revision either, because pixiv #49755474's submission time is consistent with the current image URL:
- 4/10/2015 00:11
/2015/04/10/00/11/15/
When someone tagged it waifu2x and upscaled, that was indication that the image most likely went through post-processing with those tools to produce a "superior" post of dubious quality (as waifu2x doesn't perfectly upscale art, no software really can).
We have a policy against waifu2x upscales because it is unfair towards both the artist and other uploaders who don't modify the original artist's art. You are welcome to share it in a comment if you wish, but uploading a post for it explicitly is heavily discouraged.