Hard to say, but follicular and/or sebaceous cysts are common in many dogs. But bc you say it's so soft and water like, I doubt it's sebaceous as those turn very hard. You could try putting a bit of pressure on it to see if it will release the fluid but beyond that, I'd see a vet.
__________________ ~ A friend told me I was delusional. I nearly fell off my unicorn. ~ °¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie °¨¨¨°ºOº°¨¨¨° |