Episode 21: 侵入者ルール破ってルルルルル – Shinnyūsha Rūru Yabutterururururu
(Intruders Brrrrreaking Rules)
Yuhi and co. return to the surface to do some sleuthing about Goha Yuna. However, even though they’re about to start their investigation, Yudias is nowhere to be found. As they investigate the Goha Company, a fragment of Fisher Sky, Navel No. 81, informs them that Yudias is in danger.

Script: 樋口達人 || Higuchi Tatsuto
Storyboard: 近藤信宏 || Kondo Nobuhiro
Direction: 三好正人 || Miyoshi Masato

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