Supernatural Underground Brain
白いたよ 刈る
Shiroitayo Karu

Species: Rat
Ability: Making any liquid substances
Age: Around his 30's
Location: School for the Supernatural (youkai realm)
Occupation: Chemist teacher in SSS
Theme: 禁止された知識


Personality:
Karu is considered to be a fairly pleasant person, devoted to serving Shimoyoshi and helping his students studies. Due to him monitoring the school halls every night, he is often seen being asleep in his classroom or desk. Despite his well mannered appearance, he can be dangerous based on threats that are thrown at him. Several students say he can be scary looking whenever he sits at corner of the classroom in the shadows looking at his students, while holding a syringe in his hand.

He can be enigmatic, refusing to answer any questions in relation to his past or the purpose if his chemicals or what is hiding in his lab. He is very intelligent, to the point that others have a a hard time understanding him. He is a quick thinker and is shown to placed several traps in his lab to prevent anyone one from stealing his work.



Ability:
Making any liquid substances
Karu can make all sorts of chemicals and substances from medicine to potions. His chemicals have powerful capabilities, such as making plants grow fast, changing the flavor of water and even the capability to transform one species into another. His chemicals are often dangerous, if inserting the wrong ingredients will cause some side effects to those who consume the substance.

According to his own words to Seishou, he created a rare chemical granting those who consume it great knowledge, and his knowledge may not last, indicating his ability came from him drinking the chemical and that his ability may be gone. Karu stated that the first version of this chemical lead to some memories being erased, this version of the chemical is now in Shimoyoshi's possession.

Natural Genius
Karu is said to be highly intelligent and considers other youkai less smart than him. Furthermore he uses his ability to set traps in his lab to prevent anyone from finding out what he is hiding.

Increase of sense
At one point, Karu is able to locate intruders by merely smelling and hearing from afar. It is said he created and consumed chemicals made for this ability.



Occupation:
Karu is the school's chemist teacher. He is also in charge of monitoring the school halls at night which might result in being being asleep on several times, though he is fully awake whenever he is teaching.



Possessions:
Karu owns a great number of liquid chemicals that are stored in his secret lab. No one knows what are his intentions with them or they are even safe to consume.



History:
A long time ago, Karu was once an ordinary lab rat experimented by humans at a school lab. The humans created a chemical that will give great knowledge to those who consumed it, and injected it to Karu. Due to the chemical being unfinished, this caused a side affect to Karu, giving him a humanoid body. Intrigued by this, one of the chemists tested Karu's new found knowledge by placing him in a lab where Karu studied and created chemicals that can give anyone superhuman abilities.

Becoming corrupted by his chemicals, the chemists tricked Karu into making more of these chemicals, to the point where they abused him. In one incident, Karu warned one of the chemist that the substance he created was not finished due to the rush, resulting in instead of giving one the chemist the ability to read minds, the side effects caused the death of the chemist after transforming into a mutated mindless rat, Karu was then punished by placing scars on his back. After realizing he had been used, Karu use his intelligence to escape and burned down the lab and hid into the sewers. He was eventually founded by Shimoyoshi, promising him shelter if he use his abilities for her.

Once at the Youkai Realm, Karu became a chemist and making chemicals as weapons for the war against the humans and then became a teacher one the war ended and SSS was founded by Shimoyoshi.



Relationships:
Shimoyoshi Fukuhara
Karu is devoted to the youkai goddess who found and sheltered him. He is tasked by Shimoyoshi to watch over the halls at night which he does not hesitate to do so. Karu is rumored to be making a chemical that erases memories for humans that have manage to entered the youkai realm for Shimoyoshi since it is said that her ability to remove memories are lost after an incident which everyone seem to recall but do not find the answers to who, how or why it is caused.

Satoru Ichigokei
Karu created a liquid fertilizer for Satoru if her plants die during her class. She admitted that she secretly drink the liquid, despite the fact that it is for plants and not for drinking since Satoru is literally a plant youkai.

Seishou
Seishou is the only person who Karu tells his secrets to, even showing his back scars to him at a private moment.

Tojeriko Pantoja
Karu is quite fascinated with Tojeriko's dragon body, even does multiple attempts to gain a sample of his scales, much to Tojeriko's annoyance. He even tries to dissect and/or experiment on him whenever he has the chance to which Shimoyoshi agree on since Tojeriko was formerly a human who attempted to break the youkai realm's barrier.

Nishihana, Usagi and Marko
In Diary of a Greenwood, Robyn gathers Karu, Nishihana, Usagi and Marko for a meeting discussing about their thoughts and ideals about immortality, and are seen bickering at each other, which may show that they don't get along due their own theories about immortality. Nishihana and Karu are jealous of Usagi's ability to create the hourai elixir, but explains that the elixir only extends people's lives and does not give them immortality, thus they can still die once the elixir reached it's limits.

While Marko explains morbid ways alchemist did to gain the Philosopher's Stone, an item that is said to be able to give it's user immortality but she also explains that creating the stone and it's capabilities varies, and that the one she speaks most of can only giving the user extended lives by killing a person and gaining the lives they are yet to live. The meeting ends with Karu leaving to meet up with Shimoyoshi, only to reveal to the reader that he is called to make an elixir that can revive the dead.

Nezuki
Nezuki is an anthropomorphic/mutated mouse Karu found when he was on a trip to gather ingredients in the human world. He took the mouse him and is find out by Shimoyoshi. Karu apologize for not going to her directly and ask permission to let him stay, to which Shimoyoshi agreed but has Karu in charge to take care of him. Following Gregalias' advice when he found Kuripa, Karu teaches the mouse the basics of math, reading, cooking and cleaning and naming him Nezuki.

Hebigami
Hebigami is a snake god who visits SSS for trading medicine with food for his people. Karu is suspicious towards Hebigami and the two glare at each other whenever they see each other. Another reason due to them being enemies is that snakes eats rats and mice.



Spell Cards:
Great Knowledge "Liquid of Great Secrets"

Great Knowledge "Dreamlike Transformation"

Hidden Knowledge "Otherworldy Truth"

Hidden Knowledge "Sun Drop Experiment"

Secret Knowledge "Everlasting Existence"

Secret Knowledge "Mercury Pharmacy"

Missing Knowledge "Myouga Potion"

Missing Knowledge "Lack of General Sense"

Forbidden Knowledge "Elixir of Immortality"

Forbidden Knowledge "Fountain of Life"