"I" is correct but incorrect. Jun shows up as a badass and explains that Akane and Kanami swapped identities 6 months prior due to boredom of being a genius known for one activity. However, the real Kanami wanted to permanently keep the identity Akane and with the assistance of Sakaki, they killed Kanami and ate her brain. They planned both locked rooms and faked death by re-using the real Akane's dead body from the first murder. Iria enjoys the detective show and bans Sakaki and Kanami from the island. "I" realizes his half attempted detective activities meant nothing in this nonsensical world. "I" leaves the island with Tomo.