虐待 (ぎゃくたい) Abuse, Maltreatment, Mistreatment, Cruelty
暴虐 (ぼうぎゃく) Tyranny, Outrage, Atrocity, Cruel
残虐 (ざんぎゃく) Cruelty, Brutality
残酷 (ざんこく) Cruelty, Harshness
酷い (ひどい) Cruel, Awful, Severe
冷酷 (れいこく) Cruel, Coldhearted, Relentless, Ruthless
酷 (こく) Harsh, Severe, Cruel, Terrible
過酷 (かこく) Severity, Rigor, Cruelty, Harsh