Ubau Mono Ubawareru Mono奪う者 奪われる者 (Japanese); Bereave or Bereaved; To Deprive a Deprived Person (English)

Seto Yu is a 12-year-old boy, despite being very intelligent, he is a deprived person. Abused violently by his father and beaten by debt collector regularly due to his father, his body filled with scars. One day, he is transported into a different world and he got what he needed to strike back at those who harm him or his loved ones.