Zack & Ace

From NYT and USA Today bestselling author Marie Harte.
Marines, genetic engineering, and a pack mentality in all things.
Neither human nor animal, shifters who are just friends...and more

Zack and Ace have been dancing around their "just friends" relationship for years. Being Circ means unavoidable intimacy when the mating heat strikes. They're finally nearing an understanding about what they truly mean to each other when they're stunned by Kelly, the woman they've been pining after for years. Lust and love confuse the issue. Then Kelly is captured by the enemy. Zack and Ace must come to grips with their relationship,or their difficulties will lose them the loves of their lives.

Warning: This book contains content readers may find fascinating: steamy romance with mm and mmf fun. Expect government conspiracies, rough Marines, genetic experiments, and snarky shifters. This book is not for the faint of heart.