The main theme behind Tsuritama is a very simple one, and one which is very common in media - the power of friendship. Of course, as this isn't a silly battle shounen, it is much more than a simple excuse to randomly power up a character to beat the big bad evil, but rather, is a simple and heartwarming tale of how a mysterious alien boy manages to break the barriers of a few boys, helping them form bonds that would last a lifetime, helping them to grow beyond who they are.
Beyond its excellent slice of life portion, the show also features a very bizarre plot. I often call these things silly, but it is done with some remarkable charm that I can't help but love it. Ranging from Tapioca to the D.U.C.K organization, the show mixes its 'serious' side with some very hilarious scenes, resulting in a great experience. The actual plot is pretty well done as well, resulting in a satisfying ending that perfectly concludes the series.
As yet another excellent entry into the slice of life genre, Tsuritama mixes the supernatural with strong characterization to create a hilarious and heart-warming work that can surely resonate with most.