Attended the first Kaji Kito ceremony of 2016, the “purification” rite held monthly. The daughter of Ven. Kenjo Igarashi, Kyomi J. Igarashi, wrote an Honors Thesis while at Wellesley on “The Development of Kaji Kito in Nichiren Shu Buddhism,” which remains (as far as I am aware) the lone English explanation of the rite. From her abstract:

The historical development and initial incorporation of kaji kito into Nichiren Buddhism suggest that the main objective was to bring happiness to people through the use of prayer. Analysis of kaji kito following the death of Nichiren has shown that although different methods of kaji kito have developed, this notion of bringing happiness has been maintained.

In much the way you have to empty a tea cup in order to receive more tea, Ven. Kenjo Igarashi’s Kaji Kito ceremony scoops away some of the bad karma in order to make room for good.