Kenja no Mago: Extra Story

The story is set 35 years ago, before Merlin met Shin. The problem child Merlin, the talented girl Melinda, and the prodigy Kyle are all spending their high school life at Earlshide Academy. Merlin and Melinda have long been in conflict with each other, but a certain event causes them to become closer...?

(Source: Kadokawa, translated)