Merc Storia takes places in a world where humans and monsters coexist. The protagonist, Yuu, is a healer apprentice and possesses the ability to tame monsters. In a quest to regain the memories of Merc, a girl confined in a bottle, the pair embarks on a journey.

Shy Natsu awakens as part of a group chosen to ensure the survival of humanity. Together, they have to survive on a changed Earth.

When she was a little girl, Atsuko "Akko" Kagari saw a magic show performed by a witch named Shiny Chariot. From that day on she wanted to be just like her. Enrolling at Luna Nova Magical Academy and having no magical background, can she become a witch like her idol Shiny Chariot?