In the middle of a fierce war with demons, countless artificial life forms were being created in a certain lab as weapons against the demons. Among them was an organic life form (slime) which was deemed to be a failure and discarded after repeated terrible experiments. One young man took pity on the slime girl and secretly took her under his protection. However, she had lost all trust in humans due to all the torture that she suffered during the experiments. Determined to save her life, the young man treated her with love, hoping that she would open up her heart to him one day.