Kyuutei Kagashi, [Lock] to [Release] no Nouryoku o Kakushiteitara Tsuihou Sareru: Fuuin Shiteita Maou ga Abaredashita mitai dakedo, S-Rank Boukensha to Dungeon Seiha Suru node Mou Osoi desu

The Royal Locksmith Yuri is framed for embezzlement and expelled from the Imperial Palace without being able to take over the mission of sealing the Demon King. The one who reached out to him was the S-Rank Adventurer, Astoria! Astoria had noticed Yuri's ability, who had acquired out-of-spec "Key Magic" through the Demon King sealing!?