It lowers your heart rate in about ninety seconds. There is no dialogue here, no narration, no exposition, just creatures who communicate entirely in one syllable, "-shun," the same pun that turns 絶滅危惧種 into the title itself. Thirteen episodes dropped straight onto YouTube and Twitter, which means the natural way to watch is exactly how it was designed: scrolling, half-distracted, then suddenly sitting still and paying full attention to something that never raises its voice. The endangered-species premise could have been a guilt trip, and instead it's a Kadokawa-backed brand exercise in cuteness that trusts silence to do the work. Nothing escalates, nothing resolves, nobody explains the joke. It's the show you put on at 1 a.m. when you cannot handle one more line of dialogue from anyone, fictional or otherwise, and "-shun" is somehow the most reasonable thing you've heard all day.

Zetsumetsu Kigu-shun. is a slice-of-life ONA centered on endangered species, and none of its characters speak in ordinary lines. The only word any of them ever utters is "shun." Its 13 episodes arrived online in 2018, streamed through the anime's own YouTube channel and Twitter account as well as on the YouTube channel of Kadokawa, which co-created the brand.