Reiner is half fluent in Bertolt's dialect of idiotese. As such, the muzzy sound has him making a no-nonsense sound in response, the sort that brooks no argument. "You're drinking that. I know you haven't drunk a thing since Utgard." Because that was how long Reiner hadn't drunk a thing when he had gotten here.

Reaching in, he pinches Bertolt's nose for just a moment. "Don't go to sleep yet. There's a couple of things you need to know first." At least this time his expression is somewhat apologetic. He knows Bertolt needs sleep. He certainly wants him to get his rest. But he also knows that being a warrior means that sometimes sleep has to wait for a while.