Fun at the aquarium (Patreon)

Scenario for this prompt was suggested by a Patreon user!

Chisato Nishikigi and Takina Inoue (Lycoris Recoil) are having fun at the local aquarium by watching the many fishes around, and also imitating some of them. Can you figure out which animals they're both playing out to be?

This pic was made for the Sinktember! For more information, check the post over here:

https://twitter.com/Evan_HarreyH/status/156080631950594048