Sauce?
Supposedly by amatarou, but can't find anything relevant. Image search doesn't help. Searching by filename brings up a couple of 4chan threads but never any actual sauce.
bump, try in the sad panda
Yes, it is by amatarou.
http://book.dmm.co.jp/detail/b405acmhm00288/?dmmref=aComic_List&i3_ord=31&i3_ref=list