Both in and outside of Japan, the early history of Japanese woodblock-printed children's literature continues to be insufficiently understood. Even the topic is controversial insofar as some contemporary scholars have denied the existence of a Japanese children's literature prior to the nineteenth-century importation of Western notions of the child. By examining a young boy's collection of picture books that were sealed inside a statue of the bodhisattva Jizo from 1678 to around 1980, the present article seeks to illuminate the contents and principal themes of "boys' books" an incipient form of Japanese children's literature apparently written for and consumed by children published in the Kyoto-Osaka region in the 1660s and 1670s. In particular, the article takes up the issue of extravagant representational violence in a subset of four illustrated warrior tales with obvious links to the contemporaneous sekkyo and ko-joruri puppet theaters, exploring the salient features of those works in their historical and literary contexts.