ダンジョンで成り上がれ!, Dungeon de Nariagare! - Osananajimi kara no Kirawarete Goblin ni Saekate Nakatta Ore ga, Dungeon Ruler no Shidou wo Uketara Tsuyoku Nareta no de Imouto to Musou shimasu, ダンジョンで成り上がれ！〜幼馴染からも嫌われてゴブリンにさえ勝てなかった俺が、ダンジョンルーラーの指導を受けたら強くなれたので妹と無双します〜

It's been 30 years since a dungeon was created in Japan.Kyoichi passed the same super-difficult high school as his childhood fiancé, Tsubaki, but... he was the subject of teasing in the class because he was rumored to have knelt down on his knees to a goblin.He searches the dungeon to reverse the situation, but is beaten down by a group of goblins.Thinking about his little sister tonight, he prepared himself for death...The dungeon ruler Kyoji helped me.And with this encounter, Iichi's destiny changes. Gets stronger every time you fight!The Musou dungeon walkthrough with my little sister opens!!