The journal entries are just frightening with their implications ;___; As you get to more of the 楼上 chapters the setup slowly becomes more clear. None of the characters have a split-/multiple-personality thing, but the novel does explain later why the 桥上 entries sound so disjointed.

IKR, 8 tools for eating crabs??? My relatives (who, unlike me, are practiced at eating crabs) just tear them open with their hands 😂