It was a normal day in the Armed Detective Agency. Atsushi, Kyōka and Kenji were chatting. Naomi and Haruno were playing with Mī-chan, their cat. Ranpo was eating snacks. Fukuzawa, the boss, was in his office. Kunikida and Junichiro were doing paperwork. Yosano was sorting files in shelves. Dazai was sleeping lazily. There was suddenly a noise. Fyodor broke in through the window to steal Dazai.