This is another not uncommon site in our house.  I'm not sure if Sam likes to be the "tallest" one in the house, if he feels that he is looking out and protecting us or if he just likes the smell of Ray's hair, but he loves to perch up at the top of the sofa, and sometimes on the top of Ray's head.  My guess is that sam loves the smell of Ray's hair product, and wants to show his appreciation by pawing and settling on Ray's head. 

Ray isn't feeling too swell today, but it's his birthday - Happy Birthday, babe!