Ossan Boken Sha No Okureta Eiyu Tan Kansha No Soburi Wo 1 Nichi 1 Man Kai Shiteitara, Ken Hijiri Ga Deshiri Shigan Ni Yattekita (GA Novel) [Light Novel]

[Machine Translation] Guy Gruveig was abused by his half-brother as an unfaithful child. His grandfather, an ex-adventurer who lived deep in the mountains, took him in and trained him in "swinging" as a mental and physical recuperation. After his grandfather passed away, Guy continued to swing 10,000 times a day and became an old man. One day, Guy sets out for the city to become an adventurer, as recommended by his grandfather. But what he didn't know was that he had become the strongest swordsman in the world thanks to his continuous training! Artina, the sword saint, Lilina, the receptionist, Celis, the lord... The people he helped out of the kindness of his heart, they are discovering Guy's strength...? He defeated a Cerberus of the calamity class with a single blow! Make me your apprentice! This is a tale of an old adventurer who has worked too hard, swinging his sword 10,000 times a day.

不貞の子として異母兄に虐められていたガイ・グルヴェイグ。ガイは山奥で暮らしている元冒険者の祖父に引き取られ、心身の療養で「素振り」の鍛錬をすることに。祖父が亡くなってからも、1日1万回素振りを続けていたガイはおっさんになっていた。ある日、ガイは祖父から勧められた冒険者を目指して、街に出る。だがガイだけは知らなかった―続けていた素振りのおかげで最強の剣士になっていたことを―!剣聖のアルティナ、受付嬢のリリーナ、領主のセリス...親切心で助けた人々へガイの強さがどんどんバレていき―?「一撃で災厄級のケルベロスを倒したの!?あたしを弟子にして!!」「修行中の身で良ければ一緒に剣の道を歩んでいこう」これは1日1万回の素振りで努力しすぎてしまったおっさん冒険者が、鍛え抜いた剣で強者を打ち倒す遅れた無自覚無双譚である。