The namless guy (named Cap) Is the leader of the Kazama family (The main cast) He is their fastest member (Faster then Anyone in the cast I might as well add his runing speed is stupidly good.) He also has a habit of solving problems off screen.
Also it's not really smarties vs Dummys Class S just has all the richest and most influental people in it.
I can completely understand the confusion if you haven't played the VN. If you have, though, the first episode is all Continuity Porn.