In addition to working on live-action movies of their graphic novel source material, DC Comics enjoys adapting some of their classic comic book stories as well. The most recent adaptation is Batman: The Killing Joke, which is a 30-year-old comic story that will be DC's first R-Rated animated adaptation. The story is most famous for having the Joker shooting Barbara Gordon (Batgirl's secret identity) in the stomach, which resulted in her being paralyzed. At Comic-Con 2016, there was a preview of The Killing Joke before its release date, and it was not met with the best reception, and it had nothing to do with the shooting scene.
According to iO9, there is a scene within the new animated feature previewed at Comic-Con that was very much disliked by fans. The scene was a part of a preview for the first 30 minutes of The Killing Joke, and it shows Batgirl and Batman making out and having sex.
If that sounds odd to you, then you are not alone. Most fans remember Batgirl and Robin being about the same age, and if any Batman family characters were going to hook up, it would be them. In fact, it has been depicted a few times that Dick Grayson (Robin's real name) and Barbara Gordon have had a relationship.
Yes, Batman, or Bruce Wayne, has always had a mentor relationship with Batgirl, so seeing them paired together rubs a lot of fans the wrong way. The reason why the relational element was added was the original graphic novel story was not very long, so producer Bruce Timm added on the storyline that Batman and Batgirl were seeing each other. From what it sounds like, it looks like Batgirl is being jilted by Batman. The romantic relationship between Bruce and Barbara was not in the original graphic novel.
When the clip was shown at Comic-Con, there was a Joker cosplayer who asked the writers why they would downplay Barbara Gordon, insisting that she was a powerful female character. A writer Bleeding Cool reporter Jeremy Konrad, gave a comment about how Barbara was "using sex and then pining for Bruce". This is where it gets really bad, as there is then a quote from co-screenwriter Brian Azzarello who said "wanna say that again? P***y?"
Yeah, that didn't really go so well. What the fans at Comic-Con are critical of is that the adaptation of Batman: The Killing Joke uses a common trope in comics known as "Women in Refrigerators" (WiR). This is named from an event in a Green Lantern comic in 1994 when a villain known as Major Force kills the title character's girlfriend, Alexandra DeWitt, and stuffs her body in a refrigerator. This event gets the hero to take his revenge, thus upping the drama. In the case of Batman: The Killing Joke, seeing Barbara Gordon getting shot will get Batman motivated to stop the Joker, which he would have done anyway.
Unfortunately, it is too late for DC to fix the adaptation as Batman: The Killing Joke is scheduled for its release date on July 25, 2016.