If it was Ruben then it wouldn't make sense, would it? MC should have recognized him right away.. or Ruben used a special potion on MC before he left but why would he even do that?
I think the teacher is the third party Nameless mentioned, the one that messes with the red orcs. Why else would Roghak hear about our MC (and I'm not talking about us (me) being a submissive slut for that clan) being a great herbalist but NOT about us knowing how to fight.. Because the teacher never saw us fighting I guess. I could still be wrong though..
Oh what he looks like? I think with LD's standards he is probably very hot, maybe he has a body type just like Nameless, or maybe just like Barrel or Caleb.... I think at least he has a big belly, yeah.