Dream (c!Dream) from the fanfic Of Mistakes, Regret and Freedom by orphan_account on ao3 (go check it out). Basically you're taking the place of Wilbur in the story, accidentally contractually selling yourself to Dream in exchange for L'Manberg's freedom, as you're a highly relevant member of L'Manberg, as the sibling of Wilbur.

I can't remember where the art is from but it's not mine. I've had this private for ages but you guys can chat with it now (I no longer watch any dsmp content)