>>534526998
Well, it's likely monsters do bleed and all that other stuff.
Doesn't really explain the kid asking Kris if they hurt being made out of blood, but:
The kid could just be stupid and not know monsters are like that as well.
There's different types of monsters (besides the Boss Monster stuff) and they all have different properties and attributes, which considering how fucking weird some monsters can get is entirely possible.

Now that I think about it... what if the main indicator that a Monster is a "Boss Monster" isn't just the age thing, but that they're more human(oid)?
It would be really fucked up but also make sense considering how uber powerful Humans are, the closer to "Human" you are = the stronger you are.

As for cleaning blood then idk, probably bad home life or got into fights and she had to learn how to clean blood off her clothes.
She makes a couple self harm jokes in 1-2.