Silly Nii-chan, you wouldn't be the kind of pervert that gets turned on by middle-school students, would you~Th-*thump**thump*Eeh-!?These days she's seeming more and more like an adult...That kind of situation is making your nipples hard, though, isn't it.Nii-chan is perverted!
Aren't you being a little intensive!?
In this comic, Mami misused the phrase.
Correct: デリカシーが足りないよ (literally, "You don't have any delicacy.")
It means "Aren't you being a little insensitive?"
Wrong: デリバリーが足りないよ (literally, "You don't have any delivery.")
Urgh... C-cute...!
(Is she saying "insensitive"...?)Mami is legal...!?*gulp...*Th- that's not true at all!