A Full Nelson is a wrestling hold that is applied from behind. The holder hooks his arms under his oponent's arms, then clasps his hands behind his opponent's neck. A Half Nelson uses only one arm. A Full Nelson is very difficult to escape from.
A Mrs. Nelson is also applied from behind. The arms are hooked between the woman's legs, then the hands are clasped together behind her back. Also very difficult to escape from.
Friend 2: she must be a Mrs Nelson
Friend 1: Agreed