Isekai is a subgenre of Japanese fantasy literature. The protagonist is an ordinary person who is transported to another world, summoned by magic, reincarnated as a different being, or indefinitely trapped inside a new universe. A group of people or an entire populace can also be transported into a new world. The new world must always be different from the protagonist’s homeworld. It can be ancient, magical, or futuristic. The new world can either have a similar culture and society to that of the protagonist’s, or a completely different one. According to the book Rhetorics of Fantasy by Farah Mendlesohn, there are four types of fantasy: portal fantasy, immersive fantasy, intrusion fantasy, and liminal fantasy. As Isekai involves portals leading to fantastical elements, the genre falls under the portal fantasy category. Isekai protagonists also have a quest or goal to complete by exploring the fantastical world. The common tropes of contemporary isekai stories are the main teenage protagonists from the real world, the process of being transported to a new world, video game-like world rules, growth into a legendary hero, romantic companions, and fanservice. That being said, an increasing number of isekai stories have attempted to deviate from the popular tropes. Some of the most popular isekai stories over the past decades are Magic Knight Rayearth, El Hazard: The Magnificent World, Digimon: Digital Monsters, Spirited Away, The Familiar of Zero (Zero no Tsukaima), Log Horizon, KonoSuba: God’s Blessing on this Wonderful World!, No Game No Life, Re:Zero − Starting Life in Another World, The Saga of Tanya the Evil (Youjo Senki), Overlord, That Time I Got Reincarnated as a Slime, and The Rising of Shield Hero.