Okitegami Kyouko no Iromihon

The tenth instalment of the Boukyaku Tantei Series.

The only employee of the Okitegami Detective Agency, Oyagiri Mamoru, receives a sudden threatening phone call. "If you want Okitegami Kyouko back, you'll have to come up with one billion yen." He is the only one who can rescue the lonely forgetful detective. Although he doesn't have the ...