rock fish??

https://packaged-media.redd.it/yvwbkxm79n6h1/pb/m2-res_854p.mp4?m=DASHPlaylist.mpd&var=sgpssan&v=1&e=1781244000&s=5e778eba8ed83703eef8a53eec74af64692c271d

This fish is called "Dango-uo" in Japanese (ダンゴウオ). The scientific name is "Lethotremus awae". It lives in the cold waters of Japan and it's a cute fish.