Grand Avail - Omamori no Madoushi wa Saioshi Last Boss Onii-sama wo Sukuitai

Fragile high school girl, Mana, faints while reading her beloved novel, "Gran Avel." When she regains consciousness, she finds herself reincarnated as Letitia, the younger sister of Serios, the "Ice Prince," who tragically dies as the novel's final boss. Even in her new life, Letitia remains frail, but she resolves to avoid her own death and save her beloved brother from his tragic fate. Her daily life becomes a whirlwind of creating cheat talismans, forming contracts with fluffy spirits and talking holy swords, keeping her constantly busy!