he's just having fun before the crazy period...

not much investment in my opinion. he happens to have this time free, so he wants to make the most use of it. he knows that when he's busy, he won't be able to have that much fun. if he can find a gf to stick with him through the grueling period of residency, good. if not, then too bad. basically she has to be undemanding yet be there for him at all times and caring and loyal. ask yourself if you are up for that. good luck!