In this paper, we propose bubble heap graphs. In general, social graphs show the overall relationship among nodes. For instance, from UN voting records, a social graph can be drawn, where each node stands for a UN member (e.g., US) and further two countries show similar voting patterns if the nodes corresponding to the two countries are linked each other in the graph. In such a social graph, we can clearly figure out the overall voting patterns of all UN members. However, we often focus on a particular node in the graph. It is plausible that a US citizen may have an interest in only US and he or she wants to take a look at relationships between US and each of UN members. In this case, using existing social graphs, it is hard to understand hidden insight between US and any other country. In our problem, given a country (called C) in which a user is interested, our proposed bubble heap graph effectively visualizes the relationship between C and each of UN members. For this bubble heap graph visualization, we present how to compute the similarity value between nodes, and how to visualize the bubble heap graph. In particular, to prove that our proposal is general-purpose, we applied our visualization technique to two different data sets . (1) Voting records in UN General Assembly and (2) Roll call data regarding US Senate sessions.