Kaishin is a gigantic leviathan that resides within the deepest parts of the sea until it finally came up after a 10.0 earthquake shook the seafloor waking him. Upon resurfacing it found the city of Ryūseigakure. Confused by this it began attempting to communicate with the residents. There were reports to the Ryūseikage about this. Makaze confronted the titan and after some conversation struck a deal with it. Promising to protect the seas if it helped him protect the island. At first reluctant after some time Kaishin grew to like Makaze and has become a good friend of his.