Here I have collected some examples where girls actually do look at their watches during sex to check the time.
Thus, to my opinion, this is the real reason - on the other hand (the one without a watch


Example 1
http://www.xhamster.com/movies/1304366/ ... _porn.html
at 5:03 she looks at her watch - maybe as to how long she has to hold on still (she is doing anal at this time)
Example 2
http://xhamster.com/movies/418519/my_yo ... ge_20.html
At 14:14 she looks at her watch during a short break - maybe to check how long it takes
...more examples are to follow - as they come
