This looks like ”Renpanjo”, a historical joint signature document.

The shape of the end roll of the music video for “Workin’ Hard” is strange. The names of the staff are arranged in a radial pattern. This could have been designed after an old Japanese joint signature document called “Karakasa-Renpanjo”, which was used from approximately 1336 to 1868.

Video of Zu-san and Takeo’s response and explanation for “Workin’ Hard”
I have arranged the video so that it starts with the section on the joint signature.

While I was watching Zu-san’s YouTube video on the musical perspective of “Workin’ Hard”, he said the following about the end roll:

This looks like a joint-signature document called “Karakasa-Renpanjo” that farmers used to write when they did the peasant revolt, right? If you just write the names in the usual way, the name at the top will be considered the ringleader. However, if the signatures are written in a circle in this way, the ruling class cannot capture only the representatives because they cannot identify the leader. This written way of the cast as “workers” suggests that the writers were aware of this.

I remembered that fact after hearing Zu-san’s interpretation. Yes! This is a guide on how to write an old Japanese joint-signature document.

The “Fukui Prefecture History” website has a picture of an antique joint signature document (Karakasa-Renpanjo).

www.library-archives.pref.fukui.lg.jp

『福井県史』通史編4　近世二

https://www.library-archives.pref.fukui.lg.jp/fukui/07/kenshi/T4/T4-4-01-02-02-02.htm

Ancient farmers used their ingenuity to the fullest and worked together when they were to start a riot, didn’t they?
This joint signature is called “Karakasa-Renpanjo” because it resembles Karakasa, an open umbrella. “Karakasa” means a large, paper umbrella.

In addition, a similar joint signature was used in France a long time ago, and it was called Round-robin. In the 17th and 18th centuries, farmers in France submitted a petition to the king. In response, the king executed several people who had signed the petition, including the top few names on the list. As a result, they wrote their signatures in a circle to conceal the identity of the ringleaders.

Round-robin

en.wikipedia.org

Round-robin (document) - Wikipedia

https://en.wikipedia.org/wiki/Round-robin_(document)

In Zu-san’s video, he also says this.

We usually put the director’s name first for the credits in the video, but the director is not great because everyone works hard. I wonder if the director is using a round-end credit to show that everyone, from the lighting assistant to the director, is equally important.

This is a valid point. That is a perfect expression of Fujii Kaze’s worldview.