The Author has applied a concept from computer science to the dating world.
A DFS or Depth-first Search is a method for searching certain data structures that is used to teach the concept of algorithms and graph theory to introductory computer science students. It is a simple search where you start looking at the root (top) of a graph and continue down each branch until you find your target, or reach the end and go back up to continue.
In this comic, the stick figure is using this method to prepare for a date. He starts from the top level and drills down into each category (branch) looking for a problem to prepare for. This takes a long time, so when the date arrives he is still in the process of doing his search.
This is humorous because the stick figure chose the wrong algorithm, which effectively ruined his date. He will lose his one chance at procreation, thus moving us one step closer to removing autism from the gene pool.
