In this strange world, demon creatures are tearing apart the boundaries between the real world and the demon world all the time!
A boy with no fighting ability accidentally entered the cracks in the demon world. After his sister paid a near-death price in exchange for his life, he finally woke up because of his cowardice! Fusion of the dark eyes of the DNF male mage, and after experiencing space trials again and again, he finally became the strongest magician!
"I exchange a lifetime of pain for strength, and I use my strength to protect my beloved sister!"
This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.
