Artist.
Names: "katahira" or "hiyama"
Old name: "o"
https://www.pixiv.net/users/11312586
https://www.pixiv.net/stacc/katahira-maxim
https://twitter.com/katahira24
https://twitter.com/intent/user?user_id=2425435981
https://www.pixiv.net/users/3133819
https://www.pixiv.net/stacc/2413142nsbnsb
https://twitter.com/bluestar987987
https://twitter.com/hiyama9999
