@Kazooie She's a*s but also, she had to stay in the school cause in a past chapter it said she found the world tree and the yokai girl was talking about the curse being human blood not yokai work. So she probably did something that made her indirectly responsible for it. She can't stay with her son between managing the school and fighting since they said she was the greatest Human hero or sum s*t like that. And her son is a normal boy. If he mistakenly played with the kids of back then or got caught in an attack, he's dying first most likely. She might have been helping secretly or just thought a clean cut was the best way to go. If he hated her he wouldn't try to find her mad get tangled up in the dangerous situation too early. She's not great but with every little detail being added, she just tried her best with what she got from life.