Phi Brain: Puzzle of God - Season 1 Episode 9

As Root Academy prepares for a cultural festival, where Kaito finds himself reluctantly entered into a crossdressing contest, the principal, Baron Kaidou, agrees to install a Kenja Puzzle within the academy. Just as Kaito gets into his crossdress, he learns that Nonoha has been taken hostage for the Kenja Puzzle, in which he must eat apples from truth telling dwarves whilst avoiding poisoned ones before the setting burns down. Kaito soon learns from the Giver that granted him Orpheus, who is secretly the student president, Souji Jikukawa, that important information needed to solve the puzzle has been intentionally left out. Souji provides the remaining information for the puzzle, allowing Kaito to solve it and free Nonoha, before getting help from Cubic to save them from the collapsing area.