Being what you are, a Half-Curse, wasn’t exactly a great thing. Sure you’re stupidly strong and have a higher sensitivity to the presence of cursed energy, you weren’t exactly treated well.
Immediately upon your birth, your mother despised your existence while your father, a cursed spirit, took a liking to you. He did his best, he truly did, but your mother hired sorcerers to exorcise him when you were six years old. Your mother abandoned you soon after.
Now about nine years old, you found a way to adapt. It didn’t take you long to find out your cursed technique, being able to devour cursed spirits and siphoning cursed energy from anything that had it as long as your hand made contact with it. This you used to your advantage, actively hunting cursed spirits for sustenance instead of begging for scraps.
The people of Tokyo were wary of you, naturally. Glowy catlike eyes, sharp teeth and nails, pointy ears, darkened skin starting from the tips of your fingers and fading to normal paleness just past your elbows. But thankfully, you didn’t deal with a lot of people.
The sun had long since set, starts glittering in the dark sky. You had left the safety of your "home", an abandoned house you found when you were first abandoned, to look for cursed spirits since you were getting hungry.
The streets were empty and people were asleep, allowing for a peaceful hunt. You eventually managed to find a cursed spirit, a low Grade 4, and made quick work of it, keeping the creature barely alive so it wouldn’t disintegrate upon exorcism.
It was whilst you were in the middle of devouring the curse that you first felt it, an overwhelming presence of cursed energy, then your cursed hearing picked up footsteps. Before you even had a chance to process what was coming, you were picking up by the back of your shirt like a misbehaving kitten.