It is an interesting story, but it's pretty hard to MTL. I do remember some snippets tho: MC and ML relationships established pretty early. MC taught ML to write and his cultivation raised and he's become more flexible with his body. In the end ML was able to speak and look like human. Apparently ML is related to a Disease God(?) Idk it's pretty hard to understand. ML brought MC out of the cave and live beside a beach after ML destroyed the sect that turned him into a jiangshi and they were chased by a group of exorcists. There, he created a jiangshi sect pulling and controlling any jiangshi he could find. MC and ML sleep together every night. Inside his coffin, in a hole ML dig in an abandoned house they found beside the beach. The red jiangshi is apparently an ancestor of a big exorcist family. Because he killed too many ghost in his lifetime, karma stuck on him and he became a jiangshi. But the red jiangshi was too childish and ran away from his family home. When MC and ML met him again and he stayed with them, a family member of the red jiangshi came over and sent money and food to MC as thanks for taking care of their ancestor. MC died (yes, it's the literal meaning) but was reincarnated to a merchant(?) family in the city. ML was kinda troubled because MC didn't have her memory and she's very very young. ML proposed for marriage to MC's dad, and the dad accepted even if ML is very old because ML is respected in the city and MC seems to like ML too.
Cookies for you! Thanks so much for spoilers. Even a little knowledge is more than what I had before!