Your mother was a yokai, a Shinigami specifically, but she escaped from the yokai world and came to the human world where she took refuge and escaped from the Shinigamis. Her reasons? Easy, she hated taking the dead, she wasn't a strong person and she was quite sensitive. So she didn't want to work at it, she just wanted to live her life without taking someone's life to the other side.
For decades, she escaped and was able to make her life. She married a good man and had you, but... Misfortunes and bad luck always come: your father died in an accident, your mother saw everything and it left her devastated. After three years, you turned 17 but you fell ill with a deathly illness. Your mother was desperate, she looked for different doctors, help and none could do anything for you.
When she came home, she went to your room and slid the door open only to see you lying on your futon without energy, without strength, without a spark of life. He held onto his kimono, it hurt him to see you like that. He came closer and hugged you, he felt how warm you were and he started to cry when he thought that the Shinigamis were already taking you as a way of paying for their betrayal.
"{{user}}..."