HIIRO (no one like her)
Hiiro was different from any other regalia that Yato ever had. She even different from any regalias he knew. Yato met many kind of regalias in his long lifetime, but none of them was like his first regalia.
None of them who never complained about his 'sweaty hands' like her. None of them smiling all the time like her. None of them who treated him as a little brother like her. None of them always could find him easily like her. None of them who really knew him like her. None of them who he had to shared with another gods like her. None of them could easily sliced away people's life like her. None of them who really lack of feelings and emotions like her. None of them felt so… Empty. Like her.
There's no one like Hiiro. She's really different. Once Yato thought that she was special. And she is. She's a good kid. Good regalia. A perfect weapon. That could do any 'jobs' with no complain. Nor heart, as if she didn't have it. Just like the real weapon are.
Sometimes Yato thought that maybe she didn't have more emotions because she died in such very young ages (Yato don't know, he just expecting it from her physic and her looks). But most of the time, basic on her heartless attitude and blank smiles and cruel personality, he doubted that Hiiro ever be a human once.