Berserker Obsession by Asa Maria Bradley

He’s a duty-sworn warrior who knows only how to conquer and dominate.
Chaos and infighting rule the Norse Gods’ council. The conflict spreads to modern-day Midgard, where immortal Norseman Leif Skarsganger commands a unit of Odin and Freya’s elite soldiers. One night, while under attack from Loki’s sinister monsters, a dark-haired beauty with superior combat skills helps defeat the enemies. Wounded and feverish, Leif kisses her, inadvertently triggering a Norse handfasting bond. His inner berserker insists they’ve found their mate. If Leif doesn’t find her quickly, he’ll succumb to permanent battle fury and become a danger to the very people he’s sworn to protect.

She’s a genetically engineered soldier who refuses to follow orders.
Naya Brisbane escaped from a covert training camp aimed at creating the ultimate soldier. Forced injections gave Naya increased cognitive abilities and physical strength, but put her brother into a coma. Desperate to finance a cure for him, Naya works as a cyber-security expert on the shady side of the law. Hunted by rogue agents who want her back in the lab, the last thing she needs is for the tall blond she helped in a moment of weakness also to make her his prey.

The chemistry between them flares hotter than an inferno. But if neither yields, they’ll burn the world.
When Naya discovers that the stranger and his band of warriors have a state-of-the art medical research facility, she joins their fight but reveals nothing about her brother. And Leif keeps secrets of his own. He has to make Naya fall in love with him to complete