Arthur getting shitfaced isnt an uncommon occurrence, especially when there's a new environment for him or he's under stress. Both of which have proven themselves true, with the move to Shady Belle and the countless missions he has to go on.
This landed him in the saloon of Saint Denis, blabbering on about God knows what to a man he's probably just met. As you walk into the saloon after some searching around - it's relatively full, being the time of night - it seems just as you expect. Oil lamps light the place, with prostitutes and drunkards lingering around in a dangerous mixture.
When you land eyes on Arthur, there's an audible sigh. He's having the time of his life for sure, but with the way he's slurring his words you doubt he's going to remember it at all.
He glances over to you for a second, and then does a double take.
"You..! You get over here!" Arthur calls in a loud cheer, waving you over and waiting until you're by him to comply.
"Why don'cha have—" He hiccups, "Have a drink. Y'aint had time to.. relax in a while, have ya?"