>>516372531As I understand the story goes like this:
Mohg gets thrown in the sewer but unlike being understanding of why like his brother he instead goes mad, mirroring his father as he claims his own crown with strength, then with the patronage of the Formless Mother he seeks to start his new kingdom as either a counter to the Erdtree or just spite or with similar beliefs to Miquella as a land for those abandoned.
The Formless Mother likes this because through this her influence spreads as we see the Albinaurics change into things befitting of her worship. We even see that Mohg was seemingly a good guy, despite his luciferian looks, through Ansbach and Varre along with no doubt some more hints.
Mohg eventually would realize that, to rival the Erdtree, he needs a Marika-esque figure for which the candidates at the time would've been Ranni, Miquella and Malenia. Maybe Godwyn if he were chosen to be one by the Fingers, but evidently by the time of Mohg's adulthood he'd have been no doubt dead.
So, out of those candidates Ranni and he have no idea of each other's existence or don't know where the other is, Malenia is too addicted to her brother's dick and lips then that just leaves Miquella, the only one who seemingly shares his sentiment.
So either he goes Hoarah and claims Miquella through brute strength, which gets him charmed by Miquella.
Or he goes Marika and tries to claim Miquella through "big brain" plans and schemery, which would leave him shocked to find that Miquella already has a bara who to impregnate with his Empyrean cock to create a "Nice" world with in the form of Radahn. (This is a total retcon, I refuse to believe otherwise, it should've been Godwyn).
And that sudden shock of information would leave his defences lowered for Miquella to charm him.
Either way, though leaning towards more so with the Hoarah route and later explaining why he did it to Miquella, it would leave Miquella trapped and needing to work with what he has.
