I think you ought to take a look at the Table result view, I think you're looking at the Graph result view only.
For the nodes displayed, the query is limited to 3 paths, and each of those paths is comprised of 3 nodes. If there are nodes shared among those 3 paths returned, then you may get a number of nodes < 9, so in this case 5.
As for the extra relationships you didn't specify, the browser has a functionality (turned on by default) that queries for all relationships between the nodes returned in a query, which can be useful to see how the result nodes are connected, but aren't needed in this case.
If you open the Browser Settings (gear icon on the lower left), scroll to the bottom and uncheck "Connect result nodes" then you won't see those extra relationships.