She had it under control, maybe.
The blood was making her skin and nails slippery, it was hard to tell if her skin was red and pink because she'd picked at it or if it was a residual smear of blood. The skin of her forearm was hard, almost cracked. White patches of skin peeled, she peeled it off and ripped out the tiny hairs with tweezers. Her nails would do if she was desperate, but they made it easier, cleaner.
When Yoko stabbed a cigarette into her arm she couldn't even feel it. Her boyfriend at the time made her put ice on it, but she couldn't feel that either. She traced the pad of her finger over the raw, tender to the touch skin and could feel that it was hot, put couldn't pick up the sensation of her finger at all, not even when she started to dig her nails in.
All across her body, littered with little circular scabs, barely bigger than pinpricks as she squeezed and pinched at tiny patches. Her chest littered with odd scars and she'd wake up in the morning with scabs under her nails and scabs on her scalp and scabs everywhere.
Pinching as hard as she could with her nails, ah, ah she could feel that.
Later, she would realise, that the constant picking, pulling scabs and making new ones had built up. She couldn't feel her own skin. It didn't even look like skin sometimes. Around the nerve damaged area, she could still feel the sting and ache when she prodded around it, but there were a few strips of skin where she just couldn't feel at all anymore.
She had it under control, maybe not.
It was already out of hand by the time Yoko realised it. She bought band-aids and disinfectant and even a pair of leather gloves because she just couldn't stop herself. If she thought about it deeper than a superficial level, Yoko didn't really even want to stop, though that didn't make it any less of a compulsion.
Physically, she hated it, how it (she) looked, what it (she) did to her skin.
But nothing else quite provided the same sense of emptiness, blankness and peacefulness than the trance of spending hours peeling parts of herself off, layer by layer, hair by hair, nail by nail.
After she learned she was an ajin, Yoko didn't realise immediately that her skin was clean again. She had a few other priorities at that immediate moment.
But eventually once she craved, needed that silence of her mind, absorbed in her own self-destruction, but really, self-destruction was hardly the goal, just the by-product of her chasing that state of thoughtlessness.
Yoko didn't really notice the facts one after the other, it was a sudden realisation of details all at once. Her skin was smooth. It didn't hurt to press on the skin. She could feel her own touch again.
Lucky, Yoko thought as she began to pick and pull. At least there was a quick fix to the physical drawbacks of her self-soothing (self-ruining) compulsions.
Yoko might admit that she's at peace with not having control anymore, but there's no lying to herself.
It's not like she had any in the first place.