Riku did notice her initial reaction to mentioning the name, and it made him perk a brow a bit. "I wouldn't say I really know him," he started, shrugging. "I saw him a couple times. Old guy with a pointy hat. Sora's the one that really knew him." Riku might have known him better if he had landed on the right side to start with, but hey, what was in the past was just that, no changing it. Besides, everything seemed to work out alright for the most part in the end.
But the second part, on the other hand, that just made him smirk a bit, along with yet another shrug. "Actually, unless it's one of those really annoying doors that needs more than one key, I've got it covered." And with that he held out a hand and called forth his Oblivion. No, that wasn't him killing himself or anything crazy like that, it was the last keychain he'd had on his keyblade, so that was what was easiest to call forth. He had his Way To Dawn keychain with him, too, but hey, a little more power could never hurt. Not when it came to weaponry, at least. "This'll lock doors. I just need to find the keyhole, which can be annoying since this world is way bigger than any of the ones I'd been to before."
At her introduction he gave her a quick nod, not being the sort to be all that bothered by manners, or lack there of in some cases. "I'm Riku," he said, quickly tossing his keyblade to his left hand before reaching out to shake Morgana's with his right.