He who, she had been persuaded, would avoid her as his greatest enemy, seemed, on this accidental meeting, most eager to preserve the acquaintance, and without any indelicate display of regard, or any peculiarity of manner, where their two selves only were concerned, was soliciting the good opinion of her friends, and bent on making her known to his sister.
There are no more uses of "indelicate" in the book.
Show samples from other sources
I finally made it to the landing and, with one final indelicate grunt, pulled the trunk onto it after me.
Ransom Riggs -- Miss Peregrine’s Home for Peculiar Children
It may be indelicate of me to mention it, but I seem to have been equipped at birth with the equivalent of an echo chamber in my stomach regions.