Spike, Twilight's little dragon friend/brother. I've only conversed with him a few times. He mainly stays at the crystal tree castle, previously he stayed at the library. If I was to guess, he did that to give Twilight her private/personal space when she moved into my place. I still remember him giving me a very awkward handshake when he congratulated me for being the one that Rarity chose.
nice work
So he lives there alone?