|Which Gatekeeper is the Liar?|
|Romaji Title||Usotsuki no Monban wa Dochira?|
|English Title||Which Gatekeeper is the Liar?|
|Airdate||May 22, 2014|
|Opening||Sōshō Innocence by Maaya Uchida|
|Ending||Mayonaka no Tōbō by Yuka Ōtsubo as Mahiru/Shin'ya Banba|
|Previous Episode||Episode 7|
|Next Episode||Episode 9|
Which Gatekeeper is the Liar? (嘘つきの門番はどちら?; Usotsuki no Monban wa Dochira?) is the eighth episode of the Akuma no Riddle anime series and was released on May 22, 2014.
While Isuke Inukai contacts her 'mother', who trained her to become an assassin, Nio Hashiri meets up with her superior to discuss the Black Class' current situation, learning that a typhoon is approaching the area where the Myōjō Academy is located at.
Meanwhile, Tokaku Azuma and Haru Ichinoseu are approached by Shin'ya Banba, the split personality of Mahiru Banba who appears only during the night, leading Tokaku to believe that she will be the next one to target Haru.
The next day, as Tokaku wonders what she will do when the Black Class is over, she and Haru discover an advance warning, which appears to be from Mahiru/Shin'ya, and rush back to their dorms. However, they are confronted by Isuke, the real owner of the warning, who injures Tokaku's arm. Tokaku takes Haru to the biology room, telling her to hide there whilst she goes to confront Isuke, who calls Tokaku's bluff that she is actually unable to kill anyone. With Tokaku distracted by her fight against Isuke, Shin'ya appears before Haru, declaring her intent to kill her.