One story could be about how some birds like hummingbirds drink nectar which is like a sweet 'drink' for them. They have long beaks to reach into flowers and get the nectar. Another could be about how camels can go long periods without water and then when they do drink, it's a large amount to sustain them in their arid environments. And some monkeys in the rainforest might drink water from tree hollows or from the leaves that collect rainwater.
Sure. Polar bears are a great example. They often get their water from the blood and fat of the seals they hunt. Since they live in a very cold environment where freshwater sources can be scarce, they've adapted in this way. So it's a rather unique way of getting both food and 'drink'.
No, it is not appropriate at all. Such stories involve private and sexual content that should be kept within the boundaries of a private and consensual relationship. Sharing this kind of story in public violates privacy and is not in line with good social ethics.
No. It is not proper English. The use of 'cum' in this context is vulgar, and 'ovr' is an incorrect spelling. A proper phrase would be something like 'calling him to come over for a story about sex' if that was the intended meaning, but even that would be a rather racy or inappropriate statement in most contexts.