According to some records, the Toshima clan set up a business of water transport in Tosa and Kii provinces where Tokimitsu's father Tomotsune and his grand-father Aritsune TOSHIMA were governors, respectively.
時光の父の朝経は土佐国守護、祖父の豊島有経は紀伊国守護を務めて豊島氏が土佐や紀伊へ進出して水運業を営んでいた形跡がある。