The Baraka-Mileena Pairing
I guess here's one couple where chemistry meets chemistry and perhaps, they're luckier than Liu Kang and Kitana namely Baraka ad Mileena. How? Well Baraka did grow up with Mileena under the rule of Shao Kahn and both are implied to be attracted to another. In fact, in both of their endings (non-canon), they end up ruling Outworld as emperor and empress. So much for Shao Kahn's "never turn against him" plot for Mileena. Actually, their relationship seems to flourish with the fact that they're both ugly inside out and vicious. Also it's implied that Baraka also keeps the secret of Mileena's true origin as a clone of Kitana with Tarkatan features throughout the games.
But it was placed in a sour note though in Mortal Kombat Deception/Unchained because unlike the previous games where they seem to be falling in love. Baraka did rescue her but she was having her own motives- to replace Kitana where as long as she wore her veil, people thought she was the real deal never mind that her attire is different. She took control of Edenia and feared she could not rule Edenia if she kept her relationship with Baraka so she decided to break up with him. It's highly possible that she killed his ally but Baraka didn't kill her at all. Maybe Baraka was too in love with her to kill her. Regardless, it seemed that they both reconciled to work together with Shao Kahn, only to be star-crossed as they were both killed in Armageddon after all.