4
While other children are making mistakes and delighting in each rough edge they discover in their own abilities, Medusa is harshly smoothing out the rough edges in Crona. While other children are blossoming slowly, scribbling out their names on new sheets of paper and learning to count to twenty, Crona is reading, writing, and practicing swordsmanship with small sticks, preparing for the day he becomes strong enough to wield Ragnarok.
His pronunciation is nearly flawless, since Medusa despises baby talk. And then, once he learns how to speak clearly, she teaches him when to shut up. He learns to walk with his back straight and his head down, to be hungry, to be cold. He learns to hold the mice she gives him, the white rabbits, the kittens and puppies that push at his hands and tickle his throat with their whiskers, to fight back tears when it comes time to pass them over to Ragnarok and listen as he breaks their necks.
All of these Medusa pushes into him, lessons to be ingrained into every breath.
The ability to follow, however, he learns on his own.
Without ever being instructed, he works out just the right distance to walk behind her; not too far that she turns and snaps to stop dragging his feet, not too close that she places a vector plate underneath his soles and sends him flying back...always trailing five steps behind, enough space to let her forget him, should she wish.
One day, she stops mid-stride to spare a glance over her shoulder, smirking at the way he freezes in his tracks. "You're such an obedient child, Crona. I'm pleased with you."
Lowering his gaze to hide the shining in his eyes, he kneads childish handfuls of his dress and quietly thanks her.
As she fills the entirety of his vision, this becomes his reason for being. He needs no other.