Copyright: lu over the wall
https://en.wikipedia.org/wiki/Lu_over_the_Wall
Lu over the Wall (Japanese: 夜明け告げるルーのうた, Hepburn: Yoaketsugeru Rū no Uta, literally "The song of Lu, the dawn announcer") is a 2017 Japanese animated fantasy film produced by Science Saru and released by Toho about the eponymous ningyo (mermaid).