Picasso combined themes of mythology and male sexuality in this intriguing painting. The portraits used here point at influences from the Cezanne series of bathers. Picasso's own role in the development of cubism is well known for it's links to the work of Cezanne.
The Pan Pipes makes use of a huge canvas, similar to the likes of Guernica. One advantage of that here is how these monumental figures are able to really dominate and astound the viewer, even before considering the ideas behind their construction.
Any self-reflection of personal sexuality would suggest a confidence from Picasso, his own masculinity represented by these symbols of strength.
Picasso is careful in this artwork to style his portraits in a way that helps them stand out as much as possible, and make it very clear as to where the focal point of the painting lay.