For sure there might be extra steps to get things done, but it's an option.  I think Molly counts pretty much as fae for the purposes of Winter Law anyway.

Certainly possible.

I don't think that the infection works like that. I think it's an amplification of something that is in everybody, some weakness.  And the infection acts like a reinforcement of that weakness. That's basically how it worked with Cat Sith. He hated serving Harry and the voice whispered to him to kill Harry.  When Harry points it out, Cat Sith resisted and was destroyed. I'm not sure that there is anything left of Justine.

Mab on the other hand had Molly prepared, however the Queen does that kind of thing.  It was Mab's choice where that mantle went.

We don't know much for sure about the infection, but we know that the host can recover from Beside taking control. He took control of Lea in Proven Guilty, and she bounced back.

In Battle Ground, just after Murphy is killed, Mab orders Harry to kill Molly if she doesn't survive.  She goes on to tell him why, though Molly has the makings of a good Lady, she would be horrible for everyone as Queen... What I am saying and why it has bearing, if Mab feels that way now, she felt that way then... Which is the reason why she had ordered Harry to kill Maeve, even if it wasn't him that ended up doing it.  Titania lost her daughter, she accepted Lily but for how long? Because she had many short comings, she may have had to have her killed also.. And if she wasn't satisfied with Sarissa, I don't think Titania would hesitate to order her killed.  Heck she may have wanted Lily dead, but Fix loved her and may have talked Titania out of it.

Ah, right, gotta.

Probably referencing Mab's comment in BG before the Eye showdown.  I think the point was that even if the Lady mantle chooses someone that Mab disapproves of, as long as Mab knows where it is, she can kill the new Lady in the presence of a more suitable candidate. 

My only comment would be that Mab might have to have Molly killed, rather than kill her herself, if she decided to not keep her. Mostly because Molly may still technically be mortal, and Molly didn't make a contract with Mab like Harry did.

But I think there was WoJ about Molly accepting the mantle, so maybe she's signed on and owned just like Harry.

I'm trying to figure out in my head using book evidence if the contagion *has* to be Beside. I'd prefer if it didn't.

I'd prefer if the contagion is a conduit that corrupts those it touches, changing them, but it doesn't have anything to do with Beside.

The question is, if the contagion in last call tied the beer drinkers to the essence of Dionysus, then could the nemesis contagion tie to the Lord of Slowest Terror, master of the Walkers?

It could be that the contagion is a psychic link, and the link causes behavior corruption without Beside being involved.

Beside could just be using the link to spy on some, and possess a select few that meet additional criteria.

Theory on Order of Infection

• Young Lord Raith infects himself; becomes anchor for Beside
• Lord Raith infects Kemmler
• Kemmler branch begins and ends
• Lord Raith infects Margaret Lefay
• Margaret Lefay breaks free
• Lord Raith infects Justin DuMorne
• Justin DuMorne infects Elaine Mallory
• Lord Raith infects Cowl
• Cowl infects Peabody
• Cowl infects Victor Sells
• Cowl infects Denton & the Feebs
• Cowl infects Bianca
• Cowl infects Leonid Kravos
• Cowl infects Lea
• Cowl infects Ferrovax
• Elaine infects Aurora
• Lea infects Maeve
• Lord Rath infects Madge
• Maeve infects Scarecrow
• Cowl infects Madrigal Raith
• Cowl infects Vitto Malvora
• Nemesis-controlled Lord Rath infects Justine
• Cowl infects Namshiel's Host
• Cowl infects Madeline Raith
• Cowl infects Arianna Ortega
• Maeve infects Cat Sith

My guess is that only those outside of time itself are singularities like that. I think the only good guy we've seen like that is Uriel. But maybe not even him.

I do like to think that the Walkers are singularities, and the Queens are not. It would help make sense of Harry's thought in Cold Days, where Mab was a photo, and Before was the statue itself. He senses that Mab is one thing representation of the power that transcends dimensions, whereas Before is all of that power in one being that is aware of all his other existences.

And to clarify, I mean that there could be seven branch realities, and there's a Uriel and a Before in each, and they're all aware of each of their versions, and know what they know.

LAST CALL

   “It’s laced with . . . some kind of contagion
focus, I think.”
   I nodded. She was talking about magical
contagion, not the medical kind. A contagion focus
was something that formed a link between a
smaller amount of its mass after it had been
separated from the main body. A practitioner
could use it to send magic into the main body, and
by extension into all the smaller foci, even if they
weren’t in the same physical place. It was sort of
like planting a transmitter on someone’s car so
that you could send a missile at it later.
...
   “The contagion looks like a simple compulsion
meant to make the victim drink more, but it’s really
a psychic conduit.”
...
   “A psychic conduit?” Murphy asked. “What’s
that?”
   “It’s like any electrical power line,” I said. “Except
it plugs into your mind—and whoever is on the
other end gets to decide what goes in.”
...
   “So do what you do. Put the whammy on them,
and let’s track them down.”
   I grimaced and shook my head. “I don’t dare,” I
told her. “All I’ve got to track with is the beer itself.
If I try to use it in a spell, it’ll open me up to the
conduit. It’ll be as if I drank the stuff.”
...
   “That’s what the psychic conduit links them to,” I
said. “To Dionysus. To the god of revels and
ecstatic violence.”

BATTLE GROUND

   “I am the doubt that wards away sleep. I am the
flaw that corrupts, the infected wound, the false
fork in the trail. I am the gnawer, the worm in the
book, the maggot that burrows in the mind’s eye.”
   “I am He Who Walks Beside.”

PROVEN GUILTY

   “These mortal notions,” Maeve said. “Good, evil,
love. All those other things your kind natter on
about. Are they perhaps contagious?”
   I rose with her, politely. “Some would say so,” I
told her.
   She grimaced. “In the time since her death, I
have often thought to myself that Aurora was
stricken with some mortal madness. I believe the
Queen of Air and Darkness has been taken by a
similar contagion.”

COLD DAYS

   “Sir Knight, you must have seen it. You must
have seen the contagion spreading. It has been
before your eyes for years.”
   “I haven’t seen . . .” Then I paused. My head
started adding things together. “You . . . you aren’t
talking about a physical disease, are you?”
   “Of course not,” Lily said. “It is a kind of spiritual
malady. A mental plague. An infection slowly
spreading across the earth.”
   “And . . . this plague. What does it do?” I asked.
   “It changes that which ought not change,” she
said quietly. “It destroys a father’s love for his
family by twisting it into maniacal ambition. It
distorts and corrupts the good intentions of
agents of mortal law into violence and death. It
erodes the sensible fear that keeps a weakly
talented sorcerer from reaching out for more
power, no matter how terrible the cost.”

Arianna knew, so there's a chance Nemesis knows, which means ant ally of Nemesis can be told, and they can quietly disseminate the info as much as needed. I'd say it's not much of a secret to those with the most knowledge.