In this paper, we consider an axially symmetric (2 + 1)−dimensional rotating Banados-Teitelboim-Zanelli (BTZ) black hole to investigate its interior information. First, we choose a largest space-like hyper-surface at r v = 0.45 and calculate the maximal interior volume bound by it. We found the interior volume to increase with advance time v. Similarly, the scalar quantum mode entropy is also found to increase with advance time. Next, considering two important assumptions, an evolution relation is obtained between the variation of scalar quantum mode entropy and Bekenstein Hawking entropy for an infinitesimal interval of time. In contrast to the evolution relation of higher dimensional black holes, the characteristic feature of this relation is its increase with extremely large increase in black hole mass. Moreover, this work extends the notion of black hole evaporation idea to lower space-time dimensions.