Rizzo and Kenickie, “Grease”
Rizzo and Kenickie are the couple from “Grease” with the most toxic relationship. When Rizzo realizes she might be pregnant, she tells Kenickie it’s not his child. Before the school prom, they both get into a fight. So Kenickie purposefully goes with Cha-Cha because he knows it’ll upset Rizzo while Rizzo goes with Leo because it’ll upset Kenickie.