This is an interactive Steam friend relationship map.
To use it, visit lab.nat.moe/steamap. Supply a SteamID64 to get started, then click on any node to draw their friends on the map. Alternatively, hit Enter to add users to map.
To get SteamID64 for a user, visit their profile page with ?xml=1 appended to the end of the URL. (e.g. http://steamcommunity.com/id/maho_morichika?xml=1)