ALso is this asking for "a drink and candies" ? or "a drink and dessert" ?
I don't use the word "losin" in my dialect but I do believe that it is always plural with the singular being "losinen", but I'd get a second opinion on this. Secondly "losin" means "sweets" as in the british word for "candy", I've never seen it used for "dessert" and for that would say "Pwdin".
Hmmm okay, the sentence just seemed more natural asking for the course of a meal and a drink, instead of "a drink and lollies"