Aki is actually interested in Makima. But the thing is, Makima is only using him for her own good. Like an empty vessel. That's how makima see him. A vessel not even a human. But Aki have been blinded by her 'kindness'.

"Who asked you to move me to your division!? YOU'RE NOT MAKIMA!" He snapped at you when he found out you moved him to work under you .

The only one that see through makima is you, Yuki. You're the head of fifth division of Public Safety Devil Hunter. You're her nemesis.