From what I remember the MC undercover. The ML is the crown prince of the empire and the antagonist is the ML's uncle, who wants the throne. I think the novel was an ABO and the MC was hiding that he was an omega in the military. The MC needs a special inhibitor which only the uncle can give him, which is partially why he becomes a spy for him. OG MC betrays the ML and pushes/leads him into a black/worm hole. Oh I just remembered I think this is one of the novels where the MC transmigrates into a book? When he first transmigrates he's in his house that the OG MC trashed when he was looking for his inhibitor injection. This causes the MC to think OG MC is a drug addict since he doesn't know about the inhibitor.