He stated that she was "Turning into a husk before his very eyes", so unfortunately it seems like that is the case. It was foreshadowed by her arrogance, so one did expect that she would die, but dying like that was still really underwhelming. Could have at least died while fighting after taking out a couple goons and injuring the creature. Dying like a chump felt really lame.
Yeah, we already knew that the 2 sisters are in essence vamp gods and far beyond everyone else. Even if they fought together they would have needed a miracle to survive, even against one of the sisters.
Yet, what was supposed to be a high point of the story felt utterly rushed, barley any time spend on it and just underwhelming...that vision of the nos life bevore he turned (for whatever we needed to see that) was longer than the whole fight...
And yes it was clear Callisto wouldn't win that fight, but first she didn't even sense anything than she got jumped by the lake and after running away she got jumped a second time...at least i wanted to see a desperate fight.
As for the MC...well he is present, that's the best i can say, as he does pretty much nothing.
Seeing how much time and renders were used on filler and useless banter, this just feels like a bad joke imo.
Actually Calisto sensing it last does make sense. If we imagine that it radiates an aura, with that aura getting stronger the closer you are, then the aura would affect a low level person much further than it would affect a high level one. Calisto felt it last because she was by far the highest level in the group.
Normally it should be that her senses are also the strongest do to age and powers, way better than the MC's one in fact and for some reason even Cindy which isn't even a vamp could feel it...doesn't make much sense to me.
But yeah, short of tons of dynamite that collapse the whole place like MC suggested or the two cave women killing each other, I really don't see how it would make any sense for anyone to defeat someone that one shot Calisto.
The only chance i see is, one sister kills the other and is servely weakened, than maybe the fatty with his goons and the shield shows up...but even then they shouldn't stand much of a chance, but at least they could buy enough time for the MC to run.
Or our dream girl is for whatever reason not hostile to the MC and has other plans for him.