Mob Kousei no Ore Demo Boukensha ni Nareba Riajuu ni Naremasuka?

Decades ago, dungeons, monsters, and associated catastrophes began to exist in the modern world. Adventurers and the monster cards they use to call forth summons to battle and conquer dungeons are the most significant change that came with this. A young high school student named Kitagawa Utamaro, or simply Maro, is inspired to become an adventurer after witnessing a previous classmate achieve unexpected social success among their peers by merely taking up the sport. But for Maro, it is not quite that simple. He can not get attention by simply being an adventurer in name; instead, he must use the odd and unusable monster cards he can hardly find to truly take on dungeons.