roleplay related question/concern my idea would break lore

[Ranaku]

You could play a descendant of mhach with voidsent blood in their veins. Since you seem to be already Lalafell, which are naturally descendants of mhach, it would be probably not that far fetched. I mean you will be still the most unique snowflake among them all but at least with a little tiny bit of canon lore! And with voidsent blood you can go as edgy as you want, voidsents are literally vampiric creatures so that would fit right into your concept.

But in the end, just play what makes you happy.

Edit: And don't forget your sidekick, every Velvet needs a Laphicet.