Nodding, Seamus laughed. "That's me," he agreed. "But there's no 'owing' involved." Seamus didn't tend to let people run up too much of a tab without paying it, so as far as he was concerned there was no debt to be considered. Still, he wasn't going to say no when the payment also meant company for himself.
He surveyed the options again, glancing between the ice cream and Merwyn as if he could somehow divine the other's preferences. Perhaps someone else would have gone for something relatively 'safe' so as not to risk an awkward situation - but Seamus was too Gryffindor for that. If Merwyn didn't like his suggestion then he could make his own choice. "Honey-Pistachio or Peach Ice Tea," Seamus eventually announced. "I wanted to try both, but my heart always goes for the mint ice cream." The fact that it was chocolate-mint in this case really solidified the choice.