Octopus is an interesting theme. It represents the attitude of being happy and angry and the characteristics of being aggressive. There are also many famous Kraken (the giant demon of the North Sea, which is the giant octopus in Pirates of the Caribbean) in navigation stories. Therefore, it also belongs to a common theme that is not mainstream abroad.
In Nordic mythology, there is a monster named "Kraken", which often appears on our big screen, with a camera appearance rate comparable to that of a mermaid. However, it was later proposed that this Kraken may be real, and the evidence was given, which was very shocking. Kraken first appeared 250 million years ago, but the most detailed record was in my son on the ferry in 1781.