Taking the Pearl (Gu Ling Shi Yan X Gong Wu Hou), by Ben Ren

Set in a cultivation world, this story has the shizun and Wuhou testing each other's feelings until they finally realize that the other is the one they love. The author has a wonderfully clever plot and is great at delivering surprises. Yan Hou retains the original's possessive, calculating nature, while still having genuine feelings underneath. It's also a growing-up-together story, and it's absolutely delicious.

Theme: The immortal strokes my head and grants me eternal life through marriage