When an artist draws an original character which was originally created by a different artist.
If an artist draws his own original character(s) with the borrowed character(s), or draws borrowed character(s) from more than one artist, also tag crossover.
This also covers works where an artist draws a stolen original character from another artist, where artist copied the design of other artist's OC and labelled as their own. In this case, tag that said original character with the name given by the original artist.
Note that 描いてもいいのよ is not supposed to indicate a borrowed character. It is supposed to be used to indicate the original artist is fine with others drawing their character.
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