Emma Frost of the X-Men has had a number of romantic interests over the years, ranging from the heroic to the villainous. She has even ended up entangled with Namor, Prince of Atlantis and one of Marvel's most notorious flirts.
The possible relationship between Namor and Emma Frost became a major contention point during a tumultuous time in their lives, with their affair ultimately helping set off one of Namor's most fierce and gruesome rivalries.
Namor and Emma Frost became allies during the fallout of Secret Invasion. Both invited to be members of Norman Osborn's Cabal of power players from across the Marvel Universe, Emma went to work ensuring that Namor -- himself a mutant -- would be allied with her and the X-Men if the Cabal were to fall apart. Namor agreed, becoming an ally of the mutants on Utopia. After the events of Dark X-Men, he became an official member of the team, cementing his place with the mutants for a time. In Dark X-Men: The Confession, Emma opened up about her past relationship with Namor both professionally and personally to Cyclops, who seemed to accept it and her place within Norman's Cabal.
Throughout his time with the team, however, he also repeatedly and openly hinted at his attraction to Emma, and promised that one day they would share a bed once again. At the time, Emma had been in a relationship with Cyclops, and acknowledged the attraction but didn't move forward with it. Her genuine feelings for Cyclops had become a major part of her story, especially in light of the psychic affair the pair had shared in New X-Men. Namor's flirtations became more aggressive and open during the events of Fear Itself, with Namor leaving the battle to check on her safety and preventing her from smothering a sleeping Hope Summers.
He was able to bring Emma back from the psychic haze she'd been left in after trying to telepathically confront the forces of Skandi. Commenting on the relationship she shared with Cyclops and noting that he had "married the redhead" while remaining detached from her, Namor laid the line for their romance to grow. Following the events of Schism, the flirtations were rekindled, especially when a pheromone-dosed Namor embraced her passionately in the heat of battle. Emma and Scott spoke about the brief moment together, and Scott revealed that he had complete faith that she wasn't interested in Namor -- something that shook Emma, as she'd personally hoped for a somewhat different response.
In previous years, Scott had shown greater jealousy when someone else had flirted with Jean Grey -- and yet, Namor's words about Emma seemingly not meaning as much to him rang true. Unfortunately, the problems of their romance were only compounded by the events of Avengers vs. X-Men, which resulted in both Emma and Namor being granted part of the power of the Phoenix Force. Overwhelmed and increasingly erratic, Emma alerted Namor to the runaway Avengers hiding in Wakanda and with a kiss sent him on his way -- leading to the flooding of the nation, the massacre of numerous innocents, and an extended period of conflict between Black Panther and Namor. The affair between the two resulted in chaos for everyone involved, and remains a key element of Avengers vs. X-Men.