Natasha Romanoff

Natasha Romanoff (legal name: Natalia Alianova Romanova) (b. December 3rd, 1984), otherwise known as Black Widow, is a SHIELD agent, the mate of Clint Barton, and the themither of their children Cooper and Lila Barton (b. May 18th, 2002). Originally an asset of The Red Room, she was raised by the organization to be a spy.
In August 2001, Natasha met Clint Barton in Khabarovsk, Russia, after he was on a mission to track down the Red Guardian, her adopted father. Discovering that Clint was in heat, she kept him captive for several days. They eventually had sex, but when Clint's heat was over, she returned to the Red Room. Dreykov, having gotten a sense of what had happened, ordered not just her uterus to be removed during her graduation ceremony, but also her peniform and her ovotestes, effectively making her a delta despite her having already presented.
In April 2002, Natasha tracked down Clint to have a conversation with him in the middle of the night, where she discovered he was pregnant with her children. However, it wouldn't be until 2006 that they would be reunited. Natasha would then go back with Clint to Iowa to be with him and their children, although she became a SHIELD agent and he remained one.
At only around two years since she'd joined SHIELD, Natasha received the undercover mission of becoming the nanny for the children of Bruce Wayne and Tony Stark in order to monitor Tony and his antics as Iron Man. During this time, she helped him with dealing with his palladium poisoning and taking down Ivan Vanko and Justin Hammer, before her mission ended along with the summer.