"You can get drinks if you like. I won't be partaking." he gave a rather straight forward answer.
Everyone had a different style of doing things, Koth preferred to save any drinks until after the job was done. Kept you sharp and focused, on task and ready to reaction. Considering he knew next to nothing of the man in front of him, it would also be a level of trust he wasn't quick to extend outside of his clan and people. Slipping something in a drink was an age old trick, and a dirty one, but it was effective.
"Avoid the Kewyas juice if you are going to get something. Not particularly potent, just makes you smell for a couple of days."