Ghost knifefish is common in aquarium trade. First time seeing it was on public aquarium in my hometown around 15 years ago. The way they move omni-directionally by undulating their anal fin captivated me. Image source: fisharoma This model was designed for Origami-Dan design contest, whose theme was "a design that can be folded in 15 minutes using 15 cm kami". I had sudden idea to design it while having dinner, and then proceeded to finish it that night.
Notes about origami design and fold