I've been wanting to do this forever. And by forever, I mean, before Sakurai even joined. So I decided to finally finish the concept. I hope it makes sense.
It started when I saw someone comment that you could make a periodic table with the amount of Musume members. While, it's not really true, this is sort of in the style.
Older members before Musume got colors were given colors from other H!P projects. If they never got a color, I just made them grey.
I ran into a few issues with overlapping initials so I sort of took from other letters in their name to made them work.