They’re a fey witch who changes how they look to manipulate and prank and befuddle and seduce others. Their magic is dark, illusory, spooky, and nature based.
Some thoughts:
I Want To Be Evil - Eartha Kitt
Whatever Lola Wants (Lola Gets) - Sarah Vaughan
Trust In Me (Kaa’s song from The Jungle Book)
Curveballs welcome, no wrong answers
If you don’t need lyrics, try tabletoprpgmusic.com.
I filtered by “fantasy”, “forest”, and “mystery” and got The Feywild Manor, which sounds like a decent match to your descriptors.