Origin 

Enki Sunrise's father was a cop who was killed by another cop for standing up to corruption. She carried on his tradition, becoming a police detective. When Internal Affairs called on her to secretly investigate the disappearance of Deena Pilgrim and find proof that Detective Christian Walker was in possession of powers, she readily accepted the assignment due to what happened with her father leaving her particular interest in cops who were not on the straight and narrow. She then replaced the missing Pilgrim as Walker's new partner. 

Creation 

Enki Sunrise was created by Brian Michael Bendis and Michael Avon Oeming. She was introduced in the final story arc of the second volume of Powers, setting up her role as one of the main protagonist in the third volume of Powers. 

Major Story Arcs 

The 25 Coolest Dead Super-Heroes of All Time 

Detective Enki Sunrise became Christian Walker's new partner while he and the department were neck deep in the case of the missing Deena Pilgrim and a powers-related virus that resulting in the deaths of dozens of teenage girls. In the midst of all this, Sunrise still had her own secret agenda from Internal Affairs, which was to determine whether Walker was aiding Pilgrim and if he still had powers. 
 
The crisis with the powers virus quickly escalated so severely that Sunrise's Internal Affair investigation was no longer a priority and Ana Stone, the Internal Affairs officer who put her up to it, was kicked off the case. This freed Sunrise to help tackle the situation with freed hands, and it was successfully resolved with Pilgrim's help, though this did not earn Pilgrim respect from Sunrise. Pilgrim was still a cop who went rogue. In the aftermath, Pilgrim left the police force and Sunrise became Walker's partner permanently. 
 
However, Sunrise's investigation into whether Walker still had powers continued at the secret behest of someone else in Internal Affairs.