The university is unlikely to be too keen on you permanently moving your bf into halls - for one thing, it will start to cause issues with council tax. Your flatmates may also be less keen - after all, it's an extra person making the flat more crowded and not paying any rent. If you fell out with one (or if they found out through other means), you could find them reporting you, your boyfriend out on the streets, and possibly you too, for breaking the terms of your contract.
I reckon that it would be better for your bf to move into a shared house nearby, and just stay overnight a few nights a week - unis are fine with that.