The 'girl gets 1st knot from dog story' is really ambiguous. If we assume 'knot' is some object or mark, perhaps the dog accidentally gives it to the girl while playing. For example, if the dog has a leash with a knot and it gets transferred to the girl somehow. However, this is just speculation. There could be a completely different meaning in a specific cultural or fictional context that we don't know about yet.
I'm not sure exactly what this story is about as the description is rather unclear. It could potentially be a very strange or made - up story. Maybe it's some sort of fictional tale where a girl receives something called a 'knot' from a dog in a symbolic or literal sense, but without more context it's hard to say.
Since the given title 'girl gets 1st knot from dog story' is so open - ended, it's difficult to determine precisely what it entails. It might be a story about a girl and a dog where the dog gives the girl an item that is tied in a knot for the first time. It could also be a metaphorical story where the 'knot' represents something like a bond or a problem that the girl gets from the dog. Without further details, we can only guess at the possible meanings.