Saying that he was pissed off didn't begin to cover how he was feeling. First a house elf deposited James in the room. Then he had to decipher what the hell was going on. Finally, he had to wake Remus up so he could send a Patronus, because there was no way that he was waiting for an owl to get there.
When Sirius finally arrived, he was ready to hex James. It would certainly solve the problem of what to do with him.
"Me? You think that I got him drunk, when I have classes in the morning, and do I look even slightly drunk to you?" he asked, glaring at his brother. "He got drunk with Severus and Severus decided to dump him on me before going to sleep. I suggest you wake him up and take him home, so I can go to sleep. In fact, you can just transfigure the bloody couch and stay here for all I care. I'm going to bed."