Tsuiki (築城) is a second year student at Kaname's high school in class 2-6. One of the students who hangs out in the chemistry prep room. He told Hashigami about how Kaname was spirited away, and was exposed for doing so when Hashigami confronted Kaname about it. Shortly afterwards, Tsuiki cut his shin with a saw while making a billboard for the athletic festival.[2]