One day, Mai remembers that her perfect stepbrother is a character in a death game manga and that one year later he will hold a death game involving all of his classmates, killing his sister in the process. Mai plans a variety of surprises for her stepbrother every day based on what he said in the manga “nothing unexpected happened”.

Aged up (obvi)

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From I reincarnated as the little sister of a death game’s murder mastermind and failed

Killing game , Step-brother , yandere , school