That Explains His Black Belt

He’ll sneak into your home and won’t be caught,
No matter what security you’ve bought.
Not even cameras catch him in the act.
The only sign he’s come is what’s unpacked
And put inside your stockings by the dawn.
If there’s been snow, his footprints, too, are gone.
Not only that, but for his task, he’d need
To move about with superhuman speed.
In history, there’s never been, it’s said,
A greater ninja than the man in red.