Irene Lew

She is the main female character in the original trilogy, serving as Ryu's romantic interest. She is an agent of the CIA's Secret Auxiliary Unit, working under the codename "Sea Swallow". She later appears in a revamped form in Ninja Gaiden II for the Xbox 360 under the alias Sonia. Irene is a headstrong and gutsy woman, willing to do whatever it takes to get the job done and very confident in her abilities. She is shown to be gifted with a knack for espionage. Irene is also quite skilled with firearms of different kinds of handgun to RPGs bazooka. Irene is very loving and affectionate towards Ryu Hayabusa as she soon developed feelings for him, as evidenced from when he defeated the Demon God Vazdah the first time around and ran to embraced him. In Ninja Gaiden 3: Razor's Edge, she works along side Ayane to help Ryu, worried about his cursed condition. Although the CIA doesn't trust the Ninja, she's more focused on Ryu, and Ryu alone. She and Ryu tend to keep their friends guessing, much to each other's amusement and everyone else's annoyance.