Lost Souls, also called Lost Ones and Mindless Ones in english.
Lost Souls are people who ate mermaid flesh to become immortal but turn into savage, mindless monsters that kills anything in their path. Its a side effect and the price to eat mermaid flesh. The mermaids' blood is poisonous to do this kind of damage. This can affect to animals too, a dog for example. Only the ones who gain immortality without turning into monsters are the lucky ones from suffering this dreadful fate. Even as a Lost Soul, they are still immortal, but can be killed.
Their appearance are fish human hybrid-like with a bulky body covered in veins. The hair turns into white and the faces resembles that of elderly mermaids with big bulgy eyes, monkey faced and vampire-like fangs. The skin coloring changes are random. Some are purple, green, red, blue, black and gray.
Notable Lost Souls
Towa Kannagi (Hand only)
Sakagami Headman/Isago's Husband.