Spike has often felt hindered throughout his life, especially after moving to Ponyville. He took pride in being Twilight's number one assistant, but there were plenty of times where he felt like an errand boy. One who got into situations that required him being saved. A recent development has changed things however. Not to a grand scale, but it was still significant. And he loved it. So much that he needed to enjoy it. And the night was a perfect time for it.
Art by succubisamus on derpibooru.