In keeping with the cute theme, here's a pineconefish (Monocentris japonica), known as a matsukasa-uo (マツカサウオ) in Japanese.
These adorable paddling pinecones are here in Izu all year-round, with juveniles like this one hiding in crevices and in between rocks. Adults get pretty big, say 20cm or so, and apparently head out to open water and go deep.
Their choice of habitat, coupled with a tendency to turn tail to the camera, makes it a bit of a challenge to get a nice photo of these fish.
Another point of interest...they have light-emitting organs on each side of their face (not visible in this photo).