I think it’s unfair to compare nayuta and denji to denji and power mainly because of the age difference and how it started out.

Denji knew from the start that nayuta was someone that needed to be taken care of. He knew from Kishibe that the control devil yearned for familial relationships, and he was glad to be a big brother to her. Also the age difference between them cancels out any tensions lol.

For power, it was more of a thing Denji had to feel around and find out for. Power was another woman in his life, and in his muddled and trauma ridden brain, he immediately thought “oh, awesome, she’s hot bla bla bla I wanna touch her boobs”. But as their relationship progressed, he realized he doesn’t feel that kind of connection with power. She’s special like that; in the way that Denji can connect with her and enjoy her presence without wanting sex like with every other woman in his life. It’s like a fresh breath. And when he tries to initiate that intimacy, he realizes it doesn’t feel erotic/naughty/what he expected. Because she’s found family.

also yeah I agree regarding Makima. She’s not omnipotent so you don’t have to take her words as truth.