Kappa, a mischievous monster found in Japanese folklore, supposedly lives in a stream or pond, and has webbed hands and feet so that it's good at swimming. Human hands also have an interdigital web in the early embryo, but it disappears by apoptotic programmed cell death like a tadpole's tail. The intracellular signaling pathway that triggers apoptosis has been studied well; the signal flows down the ‘cascade’ that consists of multiple caspases (Cysteine‐ASPartic proteASE) such as caspase 9 or 3 encoded by CASP9 or CASP3, respectively. This poor Kappa in this drawing has been saturated with the water flowing down the caspase cascade, and its vaunted web is in danger of disappearing by apoptosis. Designed by TRAIS Co., Ltd. (Kobe, Japan)