His Little Liar: The Yandere Snake King's Underground Captive Mate

I thought I was just helping a snake shifter learn how to flirt. Instead, the feared Snake Shifter King decided I was his mate. When I ran, he tracked me down and hauled me into his endless underground nest. "Little liar, you can't escape." And then the memory returned—years ago, he had saved me, and we had sworn to meet again. The one who broke that promise was me.