no longer human was one of my favorite books when i was a teenager, before i even really knew what it was all about. it hits different now that i can take a look at myself more clearly.
my interpretation is that yozo's shame and lack of self-worth from his father's rejection of him at a young age is reminiscent of avoidant personality disorder. this book blew up in the covid era so i've seen people with all kinds of mental illnesses claiming that yozo has whatever they suffer from so it probably doesn't even matter "what he has". it just goes to show how powerfully this book captures the shame spiral that resonates with anyone suffering from pathological self-hatred.
what stood out to me most on my 3rd time reading this is that yozo runs away from all of his problems because he refuses to accept any explanation of his behavior other than that he is the worst person to ever exist. he brings about his own destruction by believing that he deserved to be rejected by his father, and he cannot even conceive that his father could have been wrong to reject him. i always forget how brutal this book gets near the end, especially in how it diverges from how the author met his own fate. it's a bit of a shame that the weird dialogue about antonyms and synonyms precedes the real downward spiral in this book, i'm assuming it was impossible not to translate awkwardly because it disrupts the flow of the narrative every single time i read this.

this is one of the books that really got me into literature so when i re read it recently i thought it wouldnt hold up. i was pleasantly surprised and id say it actually got better on re read. its still one of my favourites and has one of my favorite endings to this day. i really like your interpretation about how his father's rejection completely morphs his self worth, its one that i agree with.