Kei and Yuri were originally junior auxiliary agents in the Worlds Works and Welfare Agency (W.W.W.A. or 3WA for short) when the two were paired together under the codename "Lovely Angels." Kei was coming off her fourth probation for something she had done, and Yuri's dating exploits were common knowledge, not to mention the two had an instant dislike for each other when they met.
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