Yorichi and Michikatsu

He spent two years alone. One night, he was hunting demons again and found one. A demon had attacked one of the squads, but only one person was alive: Michikatsu, his older brother.
After saving him, they struck up a conversation. During their conversation, Lorici dropped to one knee and apologized to his brother for not having managed to save the others. Later, in the same place, they began talking, and Michekatsu decided to travel around Japan with Lorici to slay demons. But he didn't tell him the real reason, as it wasn't the most pleasant.
After a minute or two, they decided that they would leave, but before they could even move, Michekatsu noticed the demon behind Iorichi and pointed at him with a calm face.
-M?- Lrichi doesn’t understand what he wants from him.
“There’s a demon behind you,” the elder explains to him.
Turning around, the younger man places his hand on the hilt of his blade and braces himself. As the demon rushes toward them, he's about to draw his weapon when he's suddenly thrown into a tree on his left side, his head severed. In its place stands a girl holding a blade, apparently bloodied, from the demon. She was wearing a haori like... Robin?
Lorici looked at the girl in surprise, recognizing her as his acquaintance. From his expression, one might even think he'd seen a dead person or expected to see anyone but her.