Buzou High School Freshman. A depressed and withdrawn boy, he has a vast knowledge in many fields, particularly history and literature, as a result of reading a lot of books. Because of this, he has a great potential to become a great quizzer, but being new to quizzes, he struggles in predicting the answer to a question before fully hearing it, a very important aspect in quizzes.

It is revealed in chapter 11 that although Shiki has difficulty answering questions without hearing them in full, he can answer difficult questions correctly with astounding accuracy, for as long as he hears them in full.