4. The Jaime/Cersei Rape
HBOIt would take some doing to top the creepy incestuous relationship between Jaime and Cersei Lannister in terms of taboo-breaking. It's even worse than regular incest because they're not just brother and sister, they're twins. The idea of a consensual relationship is weird enough, but it totally crosses another line in the fourth season, when Jaime rapes Cersei. In front of their inbred son's dead body. Yeah...there are are no rules left to be broken here. After Jaime returned back from being held captive and losing his hand, their relationship had been on the rocks, with Cersei giving Jaime the cold shoulder. It seems like after Joffrey's death, Jaime was so desperate to be close to his sister/lover again that he forced himself on her, presumably thinking that at some point she'd decide she actually did want to have sex with him. Some people grieve in weird ways. Can you imagine watching this scene and having your parents walk into the room? It's not just incest, or just rape, or just sex in front of a dead body. It's an unholy combination of the three, and it's genuinely uncomfortable to watch.