最悪な【マイナススキル】を持つ冒険者・アルヴィンは、厄介者と罵られ、パーティーを追放されてしまう。
絶望しながらも、スキルを消すアイテムを得られるというダンジョンの噂を聞き、無謀を承知で「ソロ」で挑むことに。
そこで神官の少女と出会った。
彼女もまたマイナススキルに苦しめられていたが、そのスキル効果を見てふと気づく…
──あれ、もしかして、シナジー発揮してない?
デメリット効果が噛み合ってプラスに!?
スキルとスキルが掛け合わさって奇跡の快進撃が始まる!
これは不幸な冒険者たちによる、究極の“支え合い”冒険譚!
Minus Skill: a negative de-buff possessed by a select few since birth. A swordsman who has one such skill is once again in the throes of being thrown out of another party. Despite his abilities, that single skill had a huge downside, which would make him a burden to any would-be adventuring partners. Sick and tired of the never-ending cycle, he has taken it upon himself to challenge a dungeon that may possess an item that could remove a skill of his. There, he meets a girl with the Priestess class who also has a Minus Skill but…