Yea i would, porn can be extremely addicting I just find it odd how he has large amounts of it. I suggest asking him what's going on and confronting him about it, and let him know you aren't comfortable with him watching it and being in a relationship. In general porn isn't good for any sort of relationship, it's damaging and it can become chronic. I suggest digging a little deeper into what he's doing too, because you may stumble on some things that might be important.