I found out this manga just yesterday. Holy shit I love this manga already, especially the beautiful artwork. It's simply stunning. There are many pages in previous chapters that I want to hang on the wall of my room.
This backstory is really great, both in the plot, emotional sense, and the artwork. I love the style of the adult versions talking while their children selves are there, it's a nice touch. I can go on if I have to list everything I love about this manga, including the comedic parts (laughs) so I'll refrain. This might become one of my favorite unknown (?) manga because of so many factors.
By the way, I kinda ship Yuki with Yatsufusa now...I understand Yatsufusa doesn't want his best friend to continue living in madness, but if he's all alone without his one and only immortal friend, won't he also be lonely and lose his mind eventually? ;w;