Immortality

The medicine was almost perfect but there was no time. He was going to die and the doctor had to save him. The cure wasn't ready, but it will have to do. The doctor administered the remedy to the man. A change occurred to the patient but before the doctor realized it was too late and the newly created monster escaped, almost killing the doctor on the way out. But what if the doctor survived and had a second chance with two siblings that contracted the same disease?

It's the a/n now! This is a demon Tanjiro and Nezuko book if you couldn't tell. But there is a twist I will let you figure out. Anyways I also made another demon Tanjiro book you should check out! Slow updates... Anyways thanks for reading! Hope u enjoy! ;}