UGH, so that Jeong Mi turned up to be like that. :///
From my previous comment in the last chapter, what I meant by "twisted reasoning" was that, either it was two things: either she realized that she was the only one human in that neighborhood, and that time would eventually consume her if she stayed there because her "dearest" friends were immortal, and that would "isolate" her from the others, later on... or two, she kidnapped a kid to make her some kind of "company". But I never put a thought that she would want to LITERALLY sacrifice a kid for a very selfish wish of becoming a vampire (although, threatening Bong Won in "becoming a hero" as an exchange still doesn't fly well with me...)
We don't know what Bong Won (or even Joon Pyo) really feels about being a vampire, even though I think the only one that has expressed some kind of rejection is Yeo Eum because of her younger sister being an old lady nowadays with serious health conditions (and Ho Seon never grew up from being a teenager, hence him being the "baby" of the group).
You cannot simply... overthrow your humanity like that. I mean, I get that you want to keep your supernatural friends... but eventually, it becomes a weight on your shoulders because you are getting older, and they don't (and viceversa).
That's the only sad part of all of this - they seem cool and chill people to hang with... but eventually reality hits you on and realize that you aren't going to stay young forever as they have. And as much as Yi Jyung feels attracted to Bong Won... I suppose that's a barriage, you know?
(I loved the neighborhood's Freddie Mercury? I simply love when authors love to input him in some sort of cameo in their titles for wacky reasons)