>>282157821
By the end Denji has completely come to see her as a mother, and is literally led by her hand. And we, of course, see him as a kid being "mentored" by Makima.
It was maybe not the smoothest transition as previously Denji was definitely crushing on her, but by the end she's "family" and this attitude carries over towards Nayuta.
This was also why it could never work out between them as Makima was not looking to be someone's "mother", she wanted an equal.