Told or Known:
Clearly automated (posts every hour at quarter till the hour), but what is it? Conceptual art, some new sort of spam, internal testing program gone rogue, or is Tumblr becoming sentient? My guess is it’s some sort of friending bot that hits the radar once an hour to harvest new friends, but that leads to the question “Why?”.
No idea, but I can at least rule out internal testing or a sentient server for you. (I hope…)
It’s Japanese, posting from the API, and claiming to be “Tumblr::Bot/0.01”.