Holy shit, does this actually have a plot anymore?
It has derailed so much and it's nothing but lowbrow smut by now.
Also, please stop calling this hentai, even hentai has a plot, this doesn't!
I really hope they get rid of the collar, what's the purpose of her being the demon lord if she is just a cat, it would be more believable if she willingly refused to use her power rather than to have it sealed away.
So Mary wants to live a peaceful life by making sure no one finds out that she is more OP than the legendary Silver Knight, yet she dress and acts as like the Silver Knight....