Having the "title for a last name" thing could still be a fun way to go about it, though. It's all in how you'd like to spin it. For example, this is a tattoo artist character. Using that, her last name could be something catchy like "Inkdancer" or "Brandweaver."
Also, just because you use that as your nameplate doesn't mean you can't have another name as well. Aliases and whatnot are also pretty common, so she could be Umi Sigilmark or whatever as her nameplate but still have a "proper" last name of Yumimoto or whatever that is only given to people she feels more comfortable with. Or it could be her "pen name" and her actual name could be something else entirely.
There's plenty of ways to go about names and explaining them if they're not "100% lore compliant."
Also, just because you use that as your nameplate doesn't mean you can't have another name as well. Aliases and whatnot are also pretty common, so she could be Umi Sigilmark or whatever as her nameplate but still have a "proper" last name of Yumimoto or whatever that is only given to people she feels more comfortable with. Or it could be her "pen name" and her actual name could be something else entirely.
There's plenty of ways to go about names and explaining them if they're not "100% lore compliant."
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