sitting
A family of figures in which the lady creates the illusion of sitting in, or actually mounts, the man's leg. Frequently used as a dramatic flourish at the end of a dance.
(from batango.com (http://www.batango.com/Loomis.htm))
(...) or in a sentada (when literally she sits on him leaning on her right leg). ([1] (http://www.tangonoticias.com/articles/a2004/sept/threemin.html))