You know, something I like about this manga is. Alright you want to raise the stakes in a shonen manga, right? So 'the world' is at stake. But 'the world' is kind of abstract. You, the reader, need specific things to make the stakes feel important. Its more about specific characters, or their growth.
This manga, meanwhile, really said 'alright. About this illness we keep mentioning. Lets sit a while. With Narumi. With these kids.'