Kimi no Tame ni Onee-chan ga Minna Koroshite ageru -Project Dia Horizon- 1 (Gangan Comics UP!)

[Machine Translation] Another World x Yandere Sister x Death Game "For you, my sister will kill for you. Reiji Kamiki, a college student who has been feeling stagnant in his life because his job search and love life have not been going well, is given the chance to be reborn in another world by a spirit that suddenly appears one day. Moreover, he was given the right to be united with his "partner of destiny" ....... He thought he was going to start a happy life, but what started was a harsh death game in which winning means eternal happiness and losing means death. Don't worry. Together with her "sister" Hilde, who shows unusual affection for Reiji whom she has never met before, they join a killing match for survival. The shivering death game spun by the bloodstained bond begins!

異世界×ヤンデレ姉×デスゲーム　「君のために、み～んなお姉ちゃんが殺してあげる。」就活も恋愛もうまくいかず人生に閉塞感を抱いていた大学生・神木怜二は、ある日、突如として現れた精霊に異世界転生のチャンスを与えられる。しかも「運命のパートナー」と結ばれる権利付きで……。幸せな人生が始まるかと思いきや、始まったのは…勝てば永遠の幸福、負ければ死亡の過酷なデスゲームだった。「心配しないで。お姉ちゃんがみ～んな殺してあげる」初対面の怜二に対して異常な愛情を示す『姉』・ヒルデとともに、生き残りを賭けた殺し合いに参加することに――。血塗られた絆が紡ぐ戦慄のデスゲーム開幕！！！