Omega Detective's Night

An exciting undercover operation between an Omega detective and a (former) Beta detective! Alpha younger man X Omega middle-aged man. Detective Ju Hyung-jJn, who has hidden his Omega identity his entire life, becomes partners with rookie detective Yun Yi-Hwan. One day, while treating his Beta-challenged partner Lee Hwan without caution, while working undercover together, something strange begins to waft in...?(Source: Ridibooks, translated)