Solving the Case is Slightly Bitter, My Sister is Super Sweet.

Summary

Summary of the Special Department: A covert special operations organization established in 1927 in the Dragon Kingdom, responsible for national security intelligence protection. Despite transforming in 1983, it didn't cease to exist but became 'invisible'. Comprised of exceptional individuals with extraordinary skills, the Special Department includes the Guard Bureau, Special Operations Bureau, and Special Department Bureau. Members are top-secret operatives prepared to sacrifice everything for national defense, possessing incredible combat abilities and legendary battle records.

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