Death March to the Parallel World Rhapsody

is a light novel series written by Ainana Hiro and illustrated by shri.

The novel series was adapted into a manga series by Aya Megumu and published by Dragon Age. It has been published in English by Yen Press since January 24, 2017. An anime adaptation has been announced, and it will be produced by Silver Link., Connect and directed by Oonuma Shin.

Plot
29-year-old programmer Suzuki Ichirou finds himself transported into a fantasy RPG. Within the game, he's a 15-year-old named Satou. At first, he thinks he's dreaming, but his experiences seem very real. Due to a powerful ability he possesses with limited use, he ends up wiping out an army of lizard men and became a high leveled adventurer. Satou decides to hide his level, and plans to live peacefully and meet new people. However, developments in the game's story, such as the return of a demon king, may throw a wrench into Satou's plans.

Official

 * Anime official website
 * Japanese Novel official website

Other Sources

 * Wikipedia