絶対にヤッてはいけない異世界召喚

College student Hiroshi Yaki has been living a mundane life, when suddenly luck struck and some guy playing a mobile game bumped into him, causing him to fall down—right in front of a train! He got sent to the world Gezeruna instead, where a beautiful girl named Ulfina needed him. To die, that is, to save the world!