In the beginning of the first episode, we see Haru end up (very briefly) at this shrine in Enoshima, in front of which people are singing some song to some actions. Is there any "meaning" to what these people are doing in from of the shrine (particularly in the real world, and out of Tsuritama-specific context)?
For what it's worth, later, we see Haru and Yuki's classmates sing the same song after Yuki gets shot by Haru's water gun, so at the very least, I'd assume that the song itself might simply be something meaningless outside of this anime-universe, but I don't know enough Japanese culture to come to conclusions I trust.