As you can see, this is under Hikaru's OC book. It doesn't have much to do with him, it's just a made up drug that he's addicted to. This chapter will contain facts about it.

. Tosui is a very, highly addictive drug when used outside of medical use. (Fact about all drugs: they can't be addicting when used when you actually need them. You become addicted when you take them even when you don't need them.)

. It was a drug created for healing purposes, and it does its job well. It is capable of healing you— physically. Some side effects of long term use is mental damage.

. It is one of those drugs that releases dopamine, the feel good hormone. So those on tosui feel really, really good.

. Withdrawal begins within twelve hours of being off of the drug for those severely addicted to the drug. Withdrawal symptoms include and can include:

. Sadness
. Hand tremors
. Nausea
. Vomiting
. Headache
. Joint pain
. Dizziness
. Excessive thirst
. Decreased hunger
. Involuntary twitching
. Chills
. Fever
. Sweating
. Night sweats
. Cold sweats
. Seizures (in severe cases due to extreme dependence on the drug)
. Diarrhea
. Excessive urination 

. The drug causes excessive urination because urinating is one of the body's ways of ridding of toxins. So it happens simply because your body is getting rid of the poison that's in your system.

. Withdrawal symptoms of tosui can last anywhere from weeks to months. Typically, within a week, the more severe/serious withdrawal symptoms are over. The less serious symptoms often remain for a month and a half, and drug craving can last for as long as six months depending on how dependent on the drug you were.

. The longest, most lingering side effect is involuntary twitching of the fingers.