My older sister is the Lycan Queen

Elara rules every werewolf pack as the Lycan Queen — the supreme Alpha no one dares to cross. But when her gentle little sister Selene is about to marry into House Vane, Elara hides her power behind a disguise as the lowest "Omega," just to test whether her future brother-in-law is worthy. What she finds is a family of vipers. The Vanes only want Selene's spirit mines and herb garden. Her fiancé Asher has already gotten Lyra, heiress of House Gale, pregnant — and now he's ready to cast Selene aside. At every turn they humiliate Elara, calling her a "low-breed" and a "stray," never suspecting the Omega they mock is the very Queen every pack kneels to. When the Vanes push too far, Elara stops hiding. The Ancient White Wolf rises, the moonlight bows, and one by one, everyone who ever hurt her sister falls to their knees. A werewolf saga of hidden identity, sisterly devotion, and a ruthless counterattack.