Isuke Inukai (犬飼 伊介; Inukai Isuke) is one of the main characters of the manga and anime series Akuma no Riddle. She is a former student of the 10th year's Black Class of Myōjō Academy who was in a competition with the other students of that class who all were set to try successfully killing Haru Ichinose where the reward was anything the assassin wishes for. The reward she requested for was enough money for herself and her parents which would be used to build a house for her parents either in the Caribbean or the Alps.
In the final episode, she is vacationing with her parents in the Caribbean, but is a little sour about not owning the beach they're on.
She has a sadistic and a somewhat narcissistic personality. Isuke is rather blunt when she speaks, and she likes to express her opinions. She also likes to command other people, such as making Haruki Sagae call her "Isuke-sama". Isuke is also easily annoyed by trivial things, and she doesn't care about school work or helping others. What also seem to annoy her is when she's not able to knock a target of hers successfully at first attempt. In such a situation Isuke even is prone to use a pistol and shoot her target, spilling blood if needed.