Omega-sama Night Club

One day, Isetani was asked to prepare an Ω from the hotel where he worked, for the sake of entertainment. When he called out to the omega who was at the meeting place, it was a different omega. However, in an unexpected turn of events, he ended up spending the night with the omega (Sei), just like that, Isetani, who was supposed to be an α, realised he took the initiative and was given obedience training. In the end, he ends up participating in an α auction...!?