Somebody else encountered this medium on Pixiv. Google Translate calls it "color ink," and Pixiv's wiki says "Tool with intense colors used in liquid-based paintings." The user in the post decided it was gouache_(medium). Should we make a note of that on the tag's wiki?
EDIT: post #2132155 (the reason I was asking!) also listed カラーインク in tye media used, but it also is tagged with コピック (copic marker. Is this particular designation just useless for tagging purposes?
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