the nightmare comes

A girl named Alya takes a day off from the school and is alone at home. She decides to take a nap but when she wakes up what she sees is totally mind-blowing and unexpected. The world is like a nightmare where there are many creatures and beasts.Her friends and family are changed into one. Alya is attacked by one but she manages to escape . Eventually she finds out that it is real and she's the one who can help save it . But how?