I think so long as the temptation to kill his father was there, he was susceptible to falling to darkness.

And he took Kaetanay's talk seriously.

That is a nightcomer, a witch devoted to Lucifer. They all have this ritualistic scarification on their breasts and genitals.

If you think you've seen Eva Green naked, like in 300, that was a body double.

I think keeping Hecate on his side and facilitating his return to his father is more primary in his mind that shallow love, IMO. I think he's using Hecate, not falling in love with her. I certainly don't think his feelings for Brona were shallow.

I believe she truly felt it was worth it to kill that man and darken her soul a touch in doing so

Death only has meaning to the devil.

Likely not, you are correct. I think if he knew he was no danger to Vanessa, or could never be a danger because of her, he might never have turned himself in to Rusk. And then he'd never face his own demons and make the final decision as to whose side he is on, which I think is a crucial step in his own possible…

Except Ethan understands the risk of her going dark better than she does apparently. But you know, he REMEMBERS using his own faith to bring her back from the brink. I mean, he taught her how to use a gun, and he recognized her life was in danger, he didn't have a problem with her getting her hands dirty, he had a…

1. Vanessa is struggling mightily against these forces

Ethan had been a sympathetic and heroic character for the entire series.

She never allowed him a glimpse of her true self.

Vanessa is drawn to broken things. And I think Victor is redeemable, that he has a good person inside him. He's just been thwarted and afraid for so long he's lost a moral compass.

That was my thought!

simply because she is female.

In another short scene, you see Ethan coming back into Malcolm's house with Vanessa running down the stairs into his arms.

And why was Lily in his flat? Why is Lily immortal now?

Yup, we were there when he bought it, prior to his trip to Africa between seasons 1 and 2. It was when he was reintroduced to Evelyn Poole.

Pining over Ethan, much like Vanessa was

He can't "unintentionally" harm Vanessa. Amunet is the mother of beasts, if anyone can control Ethan's wolf it is Vanessa. This is why he didn't harm her last season.