Original Artist: @Chaesuart (Twitter) / 33591988 (Pixiv)

Full-res, additional variations, step process overview + GIF, and PSD files available on:

Patreon > https://patreon.com/posts/64181236
FANBOX > https://zssh.fanbox.cc/posts/3586465

Gumroad (Old rewards) > https://gumroad.com/zasshu96

Twitter > twitter/z_ARTs96