What is the Batman Graphic Novel where Bruce Wayne is in love with an underage Barbara Gordon?

I recall their being a Batman Graphic Novel that featured the story of Bruce being in love with an underage (or maybe just real young) Batgirl, and Robin being jealous of this duo. I believe Batman was also portrayed as aging, any idea the title?What is the Batman Graphic Novel where Bruce Wayne is in love with an underage Barbara Gordon?
On The Pleasure of HatingWhat is the Batman Graphic Novel where Bruce Wayne is in love with an underage Barbara Gordon?
I don't think there was a specific Graphic Novel... it's more likely it was simply a subtext of the comics for a short period... as well as being something shippers wanted (especially those who go out of their way to avoid the implications of the Batman Robin slash ship)



I know the 90's animated DCAU series had a Barbara/Dick romance... and later Batman Beyond (in the same continuity) stated that Bruce and Barbara had had a fling as well -- some of Barbara's lines indicate that in hind sight she regretted the relationship seeing it as Bruce taking advantage of his mentor status (Batman Beyond is set 40-50 years after the events of the Batman series)