Initially serialized online, the novel was acquired by Enterbrain and the first volume of the light novel was released in 2012. Enjoying its reputation as a top-selling light novel series in 2015, Overlord had already caused quite a ripple in Japan before the launch of the anime and manga. Almost 7 million copies of the light novel were printed by 2018. It’s no wonder that it was adapted into a successful anime with high viewer demand not only in Japan, but also throughout the world.