Toutenism is the name of a religion based on the worship of a large selection of gods, while following a strict set of commandments.
The name of the religion is based upon its founder, Touten.
Shown by the actions of its most well known follower, Daemon Metzger, Toutenism is a fairly brutal religion. It seems that the basis for worship is to battle and slay those who don't worship the religion. Each worshipper, known as a 'brother', chooses a god or even multiple gods out of the many available.
The most notable thing shown so far is the strict following of a set of commandments, laid down by Touten himself.
So far the commandments are mostly unknown, but it has been revealed that the use of rituals seem to take a major role in the matter.
- (You can see a list of the known commandments here)