* ContractualPurity: Around the time ''Blade'' first aired, there was a flap over the fact that Takayuki Tsubaki, who plays Kenzaki, had previously appeared in a gay porn film. For a while some fans speculated that he would get [[ChuckCunninghamSyndrome quietly shuffled out of existence]], but the fact that Tsubaki returned to play Kenzaki in the final episodes of ''Series/KamenRiderDecade'' and again for ''VideoGame/KamenRiderClimaxHeroes'' proved the fears were baseless.
** Sumiko Ozawa from ''Series/KamenRiderAgito'' makes a guest appearance, with a similar enough characterisation to make her an Expy.
** Going back even further would be Tennouji Hiroshi, who used to be Muruboshi Dan a.k.a. Series/UltraSeven.
** Hirose's father is played by Jun'ichi Haruta of ''Series/DaiSentaiGoggleFive'' and ''Series/KagakuSentaiDynaman'' fame.