Things weren't exactly looking too good for Myrcella the last time we saw her. Jaime had achieved his mission of bringing her back from Dorne, and he'd confessed to her about being her father, news she took rather well. It was a sweet moment for the show, or at least as sweet as your uncle telling you that he's your father because he had sex with his twin sister can be. And then they ruined it. Because Thrones. She started bleeding, and appeared to if not die, then at least pass out, with the reveal that Ellaria had poisoned her. Although presumed dead, there wasn't actually any confirmation (in fairness, she was quite far down the pecking order in Season 5 finale ambiguous death scenes), but now thanks to these images we see that she is indeed dead, and Jaime is gonna have some explaining to do to Cersei.