The Nobles' View of Gaveston and Edward

"One of these conventions was the assumption that both masters and their close servingmen would be 'gentle'."

This quote from the Bray article encapsulates a difference between Edward and Gaveston that led to the nobles' association of their relationship with homosexuality. Assumed in non-homosexual male friendship is the idea that both men, whether equal or one possessing power over the other, come from generally the same social background. Gaveston's low birth makes his relationship with Edward suspicious? Why would Edward adopt a platonic friend whose status is so low? In this quote, Bray offers another problem the nobles had with Gaveston's birth: in their minds, his birth not only gives him no right to the titles and power he's being given, but suggests a homosexual romance with the king.