The Dragon King's Pact

In her previous life, Riley was brutally murdered by her scheming younger sister, who envied her perfect life. When she opens her eyes again, she finds she has been reborn on the crucial "Mate Selection Day." This time, her greedy sister seizes the powerful Lion King first and deliberately leaves Riley the beastman the whole clan mocks as an "underground stinkbug," acknowledged by all as the weakest. Yet no one knows that this seemingly humble, bottom-tier beastman is in truth a legendary dragon beast king of devastating power, to whom all beasts submit!