Hi, on the spot, giving ass pajarero means that they give you a spanking on the ass, mostly to mischievous children
It is not with the ass in the air. It is when someone is a man or woman gets pants or skirt without underpants or panties, either by oblivion, strange, or other circumstances of urgency or repair.
Fowler ass mean with her naked ass, for example, in the nudist beaches people bathe " to Fowler ass "