Can't believe I just saw this, an onee-sama setup where they're vampire tutors is perfect. I wonder how much older the onee-samas are though?
In terms of chapter 6's events, I gotta say Yucca's sudden shift is just weeeird. They didn't hype up her affection for Emielle nearly enough for it to make sense for her to go all crazy yandere, but I guess it gives Eve an excuse to be all cool and save her so I guess that's what the author is going for? Minus points in terms of my enjoyment for it to be so forced but I'm still gonna keep an eye on this series.