As fireflies with less light intensity move towards high intensity fireflies which depends on attractiveness and light absorption. The attractiveness is relative; it is seen in the eyes of the beholder or judged by the other fireflies. Light intensity decreases with the distance from its source, and it is also absorbed in the media, so we should allow the attractiveness to vary with the degree of absorption. In the simplest form, the light intensity I(r) varies according to the inverse square law I(r) = Is/r2. For a given medium with a fixed γ, I between two fireflies f and h varies with rfh between them i.e.