Ragnarock City is a erotic art book and yuri manga by Satoshi Urushihara, published by Gakken in 2001 in Japan. It has been released in French and German.
The story is set in a world where a large population of cyborgs and robots has inspired a fashion of near-total nudity to show that one has a fully-human body. It revolves around the character Rachel (also translated as Reichieru and Raychel), who comes to Ragnarock City, the largest city in the world, to attend college.