Thoughts..

Hiii!! The reason its called The Summer Hikaru Died is because that is when Yoshiki realized that Hikaru has been dead all this time and that the monster has replaced him during that time. Even though he did die in January, Yoshiki didn't get to mourn his death until summer.

But yoshiki knew Hikaru was dead since January because he found his corpse while searching for him on the mountain.

Another thought I had is that everyone in the village thinks that Hikaru is alive but with the way things are going especially with the company now in the mix, it seems that Hikaru(monster) will die. So it could also reference that this is the summer Hikaru will die but his family and everyone in the village will know this time

I'm afraid that might happen too.. If it happens, I'm dropping this manga. What can I do, I'm a coward.

Sick ass theory man, I honestly see that happening even with all the pain it’ll bring the readers lol

My thought process while reading was that it was called the summer hikaru died cause even when Yoshiki originally found Hikaru’s corpse, deep down he knew he had died on that mountain but he wasn’t fully willing to accept it yet or rather he was ignoring it (?) In the summer in which the story takes place, he’s come to accept “Hikaru is no longer alive, I’m learning to accept that and see ‘Hikaru’ as his own individual”

True. Yoshiki couldn’t grieve until he confronted that Hikaru had been replaced with ‘Hikaru’. How do you outwardly grieve someone that is still ‘alive’? Honestly watching his grief manifest throughout the series has been heartbreaking. He’s just a kid, Hikaru was just a kid.

I don’t blame you. I know my heart will shatter into a million pieces