I May Be a Guild Receptionist, but I'll Solo Any Boss to Clock Out on Time Guild no Uketsukejou desu ga, Zangyou wa Iya nanode Boss wo Solo Toubatsu Shiyou to Omoimasu

Alina Clover becomes an adventurers' guild receptionist, believing that—unlike the adventurers who risk their lives every day to conquer dungeons—she will enjoy a safe and comfortable career with plenty of benefits. She hates overtime work more than anything, longing for the day when she can finally clock out on time. Sadly, that day has yet to come, as she must constantly trudge through piles upon piles of paperwork. To make matters worse, when adventurers take too long to subjugate a dungeon boss, the backlog only grows, forcing Alina into even more overtime. Whenever her patience runs thin, she dons a disguise and takes care of the boss herself, soon gaining infamy as the enigmatic "Executioner." Alina has managed to keep this secret for two years—until she finishes off a boss assigned to the high-ranking party Silver Sword. Unfortunately for her, the party's eagle-eyed leader, Jade Scrade, deduces her identity, jeopardizing the receptionist's dream of a carefree life. [Written by MAL Rewrite]