Find the source of this HD sum.

The high-definition big picture of this picture is as follows, one is similar to the mobile phone wallpaper, and the other is a square big picture, which is also the highest resolution picture of this picture, namely 1080* 1920 and 1680* 1680 pixels respectively. You can collect it if you like. The picture comes from a thousand copies of Shimashima, a Japanese illustrator, published in tumblr.