I completely agree with this idea and like it a lot thank you for sharing!!!
I wanna know why ego is horny all the time and super ego wants sweets lol
It's too early for us to say but based on everything that happened so far, I'm guessing it's rooted from their repressed desires caused by their traumas. I noticed the alter responding to their own love language, triggering the switch. Mr. Benevolent is acts of service and communication, Mr. Dubious is physical touch, Mr. Savage is quality time and attention.
Putting this and that together, we can see a bit why an immortal alpha might have developed his different personas.
The mugos represents the three parts of human personality. The benevolent one is the Superego, jerk guy is the Ego, third one is the ID which might explain his erratic behaviors, and needs that were driven by basic desires like his extreme hunger.
If anyone wants to understand it more, our friendly sister google is always available.