Lactose is a sugar like fructose so I would say milk doesn't count (and it tastes sweet)
Tomato Juice (I have no idea why that doesn't count? It is a bit sweet I guess)
Non alcoholic beer- that isn't a mixer! Who is making the rules? But it is pretty sweet.
Lemon water, iced ginger tea, iced black coffee - I'm unsure of the rules and also it's kind of about palate, because I think tonic water is super sweet and not savory at all.