Merwyn wasn't legless at this point, mostly because he'd started out late after recovering from a catapletic incident that had him knocking himself unconscious against the roadside kerb. He'd been warned not to drink alcohol, but nothing made him feel better after an episode like that and alcohol at least took his mind off the fact that he was never going to fly again because of his stupid brain.
He'd started off as usual with a little group of hangers-on who had drifted away from him as soon as he'd revealed that he was a little short for a Saturday night. He'd been drinking alone at the bar ever since and was uncharacteristically morose until someone called his name. He jumped and tensed, always worried that the person calling out to him might be a disgruntled former fan, but then he caught sight of who it was - or rather, who it was made his way sure and certain into his line eyesight - and the relieved smile he gave was genuine. "Seamus!" he called back, energised again just at the idea that someone he knew remembered his name and was looking for him.
Of course, when Seamus asked him specifically to come with him to get drunk he nearly started crying. He didn't need the puppy dog eyes in the slightest, he was up and off his stool (fairly steadily) and making his way towards Seamus and upstairs both as soon as he was asked. "Of course, lead the way! What are we drinking?" he asked, his concern there about why Seamus needed to get drunk in secret but flooded out for the time being by his happines at being asked to keep company.