Wrong Way Use Healing Magic vol 8 back

Now that Nea has uncovered Usato's past and knows that he came from another world, she's hell-bent on capturing him all for herself. To do so, she's awakened a monster that for many long years has remained slumbering in the basement of her family's manor. But that monster, once sealed away by a former hero, is a dragon of pure evil known in legends for wielding catastrophic powers!