ok, so I'm too lazy to start searching for that chapter but my guess is the type and quantity of the prayer. So if they (I quite believe Shiro is a conglomerate of dogs instead of just one because they can break apart, stay like that for a long time and actually don't lose their form like the lunarians) are truly dogs -that's amazing given that we haven't seen other kind of animals- and not just parts of other people put together or something weird like that, then they definitely need something different. Shiro was put in the last part of the line because the caste system was made by humans and so they tipicaly thought dogs weren't a priority OR they simply forgot this existence, they didn't know what to do with them, again, Shiro was the only "not human soul" case. Now, Adamant is broken so of course he can't give a complete prayer but he has that power right? So mayyybe Shiro needed less of that power than humans and provided in another way so that they can be relieved...? yeah, just a guess. we don't know were Shiro came from officially. If anyone has another opinion please share it
Can someone explain to me shiro? The dog lunarian a few chapters back. If all that's remaining are the souls of kumera, how is a dog still a lunarian and in the queue if all dogs are good boys/girls. All dogs should have been first to be prayed for. and how is it that shiro was able to fade away and become nothingness after getting his cuddles with sensei in? Does that mean sensei's prayers aren't needed? Just his hugs?