Viral Agents Series by Lilith Saintcrow

After barely surviving an IED while serving his country, Reese was whisked away by a shadowy government agency and somehow... enhanced. Now he's an agent—smarter, faster, stronger, deadlier—and executes his missions with cold precision. But when he's inexplicably drawn to a down-on-her-luck waitress, Reese learns he's not the emotionless killer he thought Division had made him. One minute Holly Candless is getting fifty-buck tips from a strange but seemingly harmless customer... moreAfter barely surviving an IED while serving his country, Reese was whisked away by a shadowy government agency and somehow... enhanced. Now he's an agent—smarter, faster, stronger, deadlier—and executes his missions with cold precision. But when he's inexplicably drawn to a down-on-her-luck waitress, Reese learns he's not the emotionless killer he thought Division had made him. One minute Holly Candless is getting fifty-buck tips from a strange but seemingly harmless customer. The next, she's kidnapped, nearly killed, and rescued by Reese. Suddenly, they're on the run from the very government that wants Reese reprogrammed—and Holly dead. Now keeping Holly alive is not only Reese's primary mission, it's his sole chance at redemption... ...and their only shot at survival. less

As a genetically enhanced agent on the run, Cal has given himself one to find and protect the woman who calls herself Trinity. Yet he's not the only one looking--the shadowy government agency Division is also hot on her trail.Despite enhanced analytic and self-healing abilities, Trinity has no memory of her life before infection. Desperate to uncover her identity before deconstruction hits, she has little choice but to trust another agent--even one who has every reason to seek revenge... moreAs a genetically enhanced agent on the run, Cal has given himself one to find and protect the woman who calls herself Trinity. Yet he's not the only one looking--the shadowy government agency Division is also hot on her trail.Despite enhanced analytic and self-healing abilities, Trinity has no memory of her life before infection. Desperate to uncover her identity before deconstruction hits, she has little choice but to trust another agent--even one who has every reason to seek revenge. Every bit of trust Trinity places in smiling, lethal Cal seems to bring back a little of her humanity.Yet when he learns the truth, he will be one more deadly danger... less