In Order to Get Married, I Fought Monsters

Romance + comedy + black humor + light novel During the day, he was still an ordinary office worker, but at night he had to fight against the leader who turned into a monster. In order to survive, the leader can only be eliminated. But the new intern told me that the monster was an alien and invited me to protect the earth together. And I don't have that idea. My biggest wish is just to say goodbye to being single.