Drama CD Matantei Mayura Ragnarok 01

On the way to school, Mayura finds a week-old test with a score of zero. Theres no name on it -- whose test could it be? This drama takes place in an AU school .
Music class! Freyr is cool by elementary school standards, and Mayura brings up her case with Yamino and Fenrir.
Class starts. After a chat with the idol detective Loki, Mayura decides to solve the mystery of the test-takers identity on her own.
Mayura corners her suspect and presents her evidence with Loki presiding.
The culprit is revealed. Case closed.