And in this Story Makima took 8 yr old Denji in before everything went to shit basically whe didn't get to meet Pochita and he didn't get loansharked by the Yakuza.

Makima now has Denji as her little lover and takes care of him education wise he goes to school but technically she was ordered to hunt him down and make him her pawn... But she didn't want that and became his very early girlfriend like mother figure plus a cool older protective girlfriend is something little Denji cannot say no to.

Also for story flavour Aki is in a sense Denji's older brother/mentor figure if Makima cannot take little Denji with her.