Meet Kaito Takagi, your typical high schooler with a low profile. He spends his days exploring dungeons in Japan, hunting slimes for some extra cash. On the side, he quietly admires his childhood friend, the popular girl in class. One day, a rare golden slime shows up, and after Kaito defeats it, he finds a super valuable item—a card that can summon mythical beings! He decides to use it and summons a stunning warrior maiden. Now, Kaito has a chance to rise above his ordinary explorer life. Get ready for a modern fantasy story filled with battles!

Will Serfort dreams of keeping his promise to a childhood friend by becoming a Magia Vander, one of the mighty magicians who sit atop the Wizard's Tower. However, he is unable to cast even the simplest of spells, leaving him to fight dungeon monsters to earn credits at Regarden Magical Academy. As if that weren't enough, he finds himself putting his sword skills to the test against a bullying professor!

Duke Fleed is a survivor of the Fleed Planet who is escaped to the Earth, onboard a mysterious "spaceship", where is raised by Dr. Umon as his adoptive son, and known as Daisuke Umon. Years after his arrival, he's faced with the threat of King Vega and his army, who want to conquer the Earth. With his friends Koji and Hikaru (and later his younger sister Maria Grace), Duke decides to fight back using his best weapon - the almighty Grendizer.

In a world of anthropomorphic animals, Belle Lablac was born as the only human being. Having no fangs, fur, or scales, she was called "Faceless," and she lived a lonely life with no one else she could identify with. "I want to be part of the world..." With such longing in her heart, she decides to set out on a journey to find her roots, carrying the Runding, a great sword as tall as she is. She doesn't know how many adversities await her along the way...