Sakurifaisu (死に手 《サクリファイス》)
After being warned about the craftiness of werebeasts, Shiro and Sora discover a hidden library that helps them prepare for an upcoming game.
They are both NEETs and Hikikomoris… but on the internet, the genius gamer siblings Sora and Shiro are known as the undefeatable “__” (blank). Sora and Shiro’s talents and skills are so abnormally good they are considered as urban legend. One day a young boy Teto appears before them, claiming to be “One’s Lord”.