There's only 3 non-Vocaloid posts on Natunashi's twitter, so it didn't feel like an entirely separate entry was warranted, so I just posted them here.
From here on out, it's 90 chapters of just Kasane Teto x Adachi Rei yuri!
Source
Tanu's the one that looks like a tanuki, they're a yuri mangaka that publishes under the name Yuni.
Negi is the black haired one, and yoorie wants to know if Negi has any other aliases, like Tanu does, but I've not been able to find any...
So far, I haven't been able to find any posts publicly linking Negi to another handle. But confirming that would take scrolling through all 2000 tweets of their shared account.
It could be that they want to keep things private, like Tanu did before her reveal?