So, currently this artist is tagged as teru_ryuuji. However, if you go to their webpage's profile page, it says "輝竜司 - きりゅうつかさ (Tsukasa Kiryu)". Following Danbooru's romanization standards, the correct tag, it seems, should be kiryuu_tsukasa. However, it turns out there is already a kiryuu_tsukasa... as a character tag.
This artist's webpage is named Citrocube, so I think it would be best to rename the artist tag to kiryuu_tsukasa_(citrocube) and move the wiki article as appropriate.
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