The Kappas are water demons in Japanese mythology.
List of Demons from the Middle East and Asia
Many of what are considered “evil spirits” within Middle Eastern & Asian culture – and especially in Hinduism – are known as such because Christianity adapted their gods/goddesses as foes to their true God. This is a common thread throughout history – one culture adopts another’s deities as adversaries of their gods/goddesses. In this regard, “evil” is relative. That’s not to say that many of these supernatural beings don’t have destructive sides – but whether it is fair to classify them as “demons” is debatable.