Beloved Lion and Omega Cage

Your whole heart will be swallowed up -- Omori Private Academy, where elite beastman alphas attend. Otani Yuu, a human omega, is the only omega scholarship student at this academy. He wears a chastity belt and is used as live bait for the alphas' desires in "Estrus Endurance Training" during his rut ​​season. One day, Mikimoto Shiou, the heir to the lion tribe and dorm supervisor, appears before Yuu...

(Source: MUGENUP, translated)