Gintama: "Let's drink away the year's woes at the Year-End party!"

The next morning, Gin-san wakes up with a hangover and finds himself in a... strange bedroom... Has Gin-san made an error in a single night with 6 familiar faces!? and a strange new face..! An unprecedented scandal comes to light as he looks around in silent shock and with a headache as everyone else in the room was sleeping still