Isekai Munchkin: HP1 no Mama de Saikyou Saisoku Dungeon Kouryaku  Play Trailer

Otherworldly Munchkin, Another World Munchkin: Conquering the Dungeon as the Strongest and the Fastest with Only 1 HP, 異世界マンチキン　ーHP1のままで最強最速ダンジョン攻略ー, Otherworldly Munchkin: Let's Speedrun the Dungeon with Only 1 HP!, 異世界マンチキン ―HP1のままで最強最速ダンジョン攻略―

Yukito Kirihara is a 16 year old who values his younger sister Sana more than anyone else in the world. One day, an ogre appears outside their home seeking Sana, which leads Yukito to risk his life to protect her. After being killed, he is given the option of being reincarnated by a mysterious woman who hands him a book containing information about himself and Sana. Despite having only one health point, Yukito embarks on a quest to locate Sana and save them both.