Then went and looked up qwerty's Mushishi fic, and was puzzled. Who are these people? Who's Tanyu? Track her back to vol 2 (read in translation, so I'm intensely bothered by not knowing is it Tan'yu or Ta'nyu.) I've heard of this Adashino but have I ever met him? Mh yes, back in 4, not named, in an unmarked scene shift inserted between unmarked flashbacks. Ginko doesn't remark him specially so neither did I. The paleness of the human relations may owe to English reading: the emotional distance of the narration is trebled by the oddness of the English translation. (Note that the translator and editor were the same guy, which I only approve of when the translator is a good writer; and it still didn't stop the lettering guys from breaking up the Japanese names wrong.)
But some of it is innate to the manga. These guys are figures in a landscape, where the land itself reduces the humans and mushi in it to a smaller size. Small sadness, small happiness, small tragedies: always against a background of something larger. So Ginko's necessarily wandering life, the inability of a mushishi to settle anywhere because of the negative effects his presence has on the world: it's mentioned and dropped, it's not an ongoing angsty theme the way angst tends to be in works aimed at adolescents. There are mushi to pursue. He pursues them, a small figure seen walking along a mountain trail.
The different sense of proportion in Mushishi is exhilarating after the up-close emotional focus of regular shoujo or even the sub-textually thrumming trauma of the Saiyuki guys. This feels closer to mono no aware than being invited to admire the spoiled brat Genji, stage front and centre, feeling sorry for himself because the transience of all things means he can't have what he wants. (And of course he doesn't want what he has-- that would be vulgar.) Hard to say, of course; grasping Japanese concepts is like hearing Japanese liquids. The Anglo ear insists it's an l or an r or maybe a d, as per, and it's really something else entirely.