[Demon Slayer] The Blue Flower

Mermaid blood is a cure-all, but the Creator is fair. Mermaids can heal others, but their own wounds take a very long time to heal. What have I forgotten? What have I gained? And what have I lost? "Lord Muzan, I may have found a clue to the Blue Spider Lily. Just, just give me a little more of your blood..." "I'll help you, trust me. But you have to help me too." The mermaid beside him kept talking to herself, but he had no strength at all and couldn't speak. X The protagonist is very weak. They do have abilities, but those come with major side effects, especially for the protagonist. The protagonist isn't the Blue Spider Lily, just an imperfect substitute, more or less. No CP for now, feel free to pick a ship. The author is busy, so updates will be whenever possible. If you can't accept that, please go back. Lastly, this story came from a sudden idea, so please excuse the many plot holes. You can't read it here anymore! Search for Qing Man on Lofter to read it! Theme: What you lose will return in another form