We focus on mobile P2P multicast, in which mobile end nodes not only act as receivers but also relay the received stream forward to others. In mobile P2P multicast, negative effects caused by the change of available bandwidth and the disconnection of mobile nodes are propagated to the downstream nodes. To solve this problem, we developed a novel node-allocation framework using the multidimensional context parameters of each mobile node, which include available bandwidth, disconnection rate, and the remaining battery capacity. Considering the significance of each parameter, our method integrates these parameters into a single parameter called relay ability. Taking the relay ability into account, each node is allocated to the multicast topology to minimize the negative effects mentioned above. To test our method, we applied our framework to conventional P2P multicast topology and show the results from comparative evaluations through computer simulation.