by how much his apartment has been accessed by other people im guessing its gone but afaik its never been mentioned again in the manhwa??
Haewon put that diary in a box and never touched it again. At the end of volume 1, Wujin finds it while cleaning Haewon’s apartment. There, he reads what Taeshin wrote—things like, "Haewon, if you ever meet him, run." But Wujin goes up to the rooftop and burns the diary before Haewon can see it, for two reasons:
1. To erase the evidence.
2. To make sure Haewon doesn’t run away from him.
This also hits a sensitive spot for him—the fact that people see him as a monster.
what happened to the notes/diary left by the dead friend? it should have been checked by MC when he kinda suspected and connected lines of wujin related to the friends death, yet he didnt bother with it at all which is such a really big plot hole