When you saw the title, did you think that this is a fanfic where the male protagonist is Uncle Ou? Then you are overthinking it.
This is a prostitution novel disguised as Uncle Ou, hee hee
Ever since she came to All Might for a commission four years ago, Saionji Qing has always paid attention to his personal safety and health. The biggest problem she faced was not his health, but that she could not find Uncle Ou who flew around every day!
As for Saionji Qing, she probably holds two big hammers that are heavier than her and wears a small skirt.
Intention: Fall in love, reverse crush