The novella is based on real events. The main hero of the novella “Enemy or Brother” is a sniper of the DPR militia with the call sign “The Sullen.” He is a brave warrior with solid combat experience. Opposing him is a young, but skilled and ambitious sniper of the Armed Forces of Ukraine. Who will win this merciless battle in Donbas? What does fratricidal war bring? Where does cruelty lead, and is there room for mercy in the heart of a professional soldier? Through the actions of the heroes, the author tells an engaging story about finding a compromise between duty, professionalism, and humanity.