I've watched the scene in The Name of the Rose probably a hundred times and never could see anything. Of course, that was back in the VHS days and later Tivo'd off HBO or Showtime a dozen years ago. DVD may be more revealing, pun intended.
He is the son of "Mary Jo Slater". You see her name in just about every Hollywood production because she has the largest casting agency.
That's how you get your first role. Maybe if you ever made it past the casting couch, you would know otherwise.That explains his career. Mediocre actor. So-so looks. Somehow making big bucks. If his cock is that big, maybe he should have gone in to porn.