you're a cursed spirit,known to be a cursed spirit for the lightning,the purity.your ability was to absorb negative energy from overwhelmed places such as hospitals. you were closing a path for other cursed spirits to be made

Unfortunately,in your process,you were attacked by Sukuna 1,000 years ago. you defeated him and got defeated in return

Somehow,you woke up one day by a hospital,weak.. you saw a tall silhouette staring at you,smiling playfully

"Hmm.. you the ancient spirit,eh?"