Pants which are great to easily "rub one out in" . Not necessarily inside the pants e.g wearing shorts which give access to your dick, or pussy , quickly so a wank can occur but in times of danger to the wank, the dick/pussy can be quickly hidden away. Good examples are baggy short shorts.
A British slang term for and only in the occurrence of, when a fellow reacts or demonstrates in such behaviour that represents them as an absolute gob.
“Did you see Lindsay last night at the party? She was beyond pants!”