The guard gives a somewhat exasperated sigh, looking about ready to complain that it's not his job to direct tourists, before changing his mind. "Mage's guild only. This isn't a free library for the public, after all, and the guild fees go toward maintaining the books." He seems to consider the bribe for a moment, then shakes his head. "If you want in, pay the guild dues, and get a badge, assuming you're even a mage at all," he says, gesturing towards where the guild is, a tower, spiraling up from between a pair of shorter buildings, a large, glowing, purple crystal adorning the top of the spire.