The Spread Shot of Kasen Ibaraki from the world delirious with eternal summer (a Touhou LW original). She guides Manzairaku, the strange fish, in this attack. Everyone thinks Manzairaku is a fish, but Kasen has her doubts. While Kasen can communicate with animals, she struggles to comprehend the thoughts and feelings of fish. She can understand Manzairaku perfectly, so it must be some other kind of animal.

The Focus Shot of Kasen Ibaraki from the world delirious with eternal summer (a Touhou LW original). She rides Manzairaku, the strange fish, in this attack. Everyone in Gensokyo knows Kasen as the animal-loving hermit. Her love for animals is equal to if not deeper than Satori's, the mistress of the Palace of the Earth Spirits. She's also skilled at fighting alongside animals and is able to perfectly coordinate their attacks. She's so in sync with her pets that she immediately knows when Manzairaku wants to play in the ocean.

A Spell Card of Kasen Ibaraki from the world delirious with eternal summer (a Touhou LW original). She trains Manzairaku, the strange fish, in this attack. Animals can become beast youkai, and some even have the potential to become greater youkai. However, perhaps the same could be said for every kind of being that isn't human. It's possible that cryptids and other unidentified creatures are actually animals that have turned into youkai. One can only hope that they listen to the hermit's teachings before the humans eradicate them...

A Spell Card of Kasen Ibaraki from the world delirious with eternal summer (a Touhou LW original). She unleashes the power of a sea-dwelling dragon in this attack. Dragons are one of the most well-known youkai of the sea. They famously live in the Dragon Palace at the bottom of the ocean. However, Kasen also keeps a dragon as a pet, so perhaps they are animals as well. It's also said that dragons live in the sky, the rain, or the sea, depending on their age. Kasen's world is practically covered in water, so even bigger dragons might lurk beneath the waves there.

The Last Word of Kasen Ibaraki from the world delirious with eternal summer (a Touhou LW original). She begins to unravel the mystery of why deep-sea animals become so large. Oni are also supposed to be really big, but in Gensokyo, this is only ever shown by Suika Ibuki. In Japanese, the word "oni" is used as a prefix to indicate a particularly large species of animal. For example, the great barracuda is called an "oni-kasuma" in Japanese. However, this probably isn't why Kasen decided to investigate this mystery since she's a hermit, not an oni. It's speculated that sea animals tend to be larger in deeper water due to food scarcity, or, in other words, the density of lifeforms. The density of temperament is probably connected, too. Kasen hopes that by unraveling this mystery, she might be able to figure out what's wrong with the temperament in her world.