Female Vigina Hair I Saw My Brother Rub My Female Kittens Lower Belly And Vigina Opened And Secreted A Weird Liquid Why?

I saw my brother rub my female kittens lower belly and vigina opened and secreted a weird liquid Why? - female vigina hair

In addition, meowed as if in pain, but the toes slightly outward, as they enjoyed it and stop beating Venn to my brother, then I do not know if it's because of the pain or anything or anyone can tell me what happened to him