The single worst part about vampire sex is being the one who has to clean up afterwards.
Better tackle this one by character...
Aidan: 'And in the event of my absence, the part of your blood doll will be filled by a sudden realization of your monstrosity.'
Somehow, I never pictured him as someone who would produce another vampire voluntarily -- but as he's said, we didn't know him back then and the Aidan of the 30s is, put mildly, not a particularly nice guy. Last season he got to work on his daddy issues and this season he gets to work on -- his daddy issues, only from the position of the dad. Is it any coincidence that the central power in the current problem is named Mother?
By the way, is that mobster going to stay down? Rebecca proved some time can pass between death and undeath, so they may be treating him as an 'we'll get around to it' issue. I doubt he'll take the treatment well...
Josh: Okay -- purebreds. This brings up last season's question of two werewolves having children and the mother shifting when the fetus does. If that's what happened here, then we're looking at the results. Or are Conner and Ren members of whatever the original werewolf bloodline is -- the Family Zero for the curse vector? If Josh's brains kick in before it's too late, he'll have a few questions about genealogy.
(And for the record, that was in fact the most pitiful lab in the history of mad science.)
Putting aside the upcoming deadly issue of 'Humanity is a skin we're trying to shed' until it threatens to induce fatalities, Josh's central problem in any medical exams is that at the moment he most needs to study the rapidly emerging data, he's providing it. What's needed here is a medical professional they can trust to watch all four changing and isolate the common factors. Of course, we now know someone who fits the bill -- but she doesn't know what Josh is, and the next entry probably means she's about to have her own problems...
Sally: Her season's arc theme doesn't seem to be temptation as much as it is jealousy. Whatever you have, she wants. Especially if she can't have it -- and as a ghost, the things she can't have include pretty much everything. I think she's reached the point where she'll be running on pure green fuel: whatever you've got, I take for myself, and it's only right because I was cheated of my chance to have it the first time and for having given up my door, I am that much more entitled than you. It's easy to see her running wild with body jumps to the point where she tackles a roommate because hey, she's never been a vampire or werewolf before. (Assuming this is even possible.) We know Ms. Hospital Awkward Of 2012 can block a takeover, but if Sally becomes jealous enough there, that old standby poltergeist power is still on tap.
We've seen what happens when Sally loses it. We're starting to get hints at the nightmare of Aidan being out of control. All we need now is for Josh to officially form a pack and we'll be at the core of despair a few episodes early.
Hooray for It Gets Worse, the official trope of the show!
By the way, what are the odds that a decent security system tracked whose card opened that door?