Osaka Aquarium is one of the largest aquariums in the world. Eight floors of underwater life at various water pressures, with one large tank in the center you walk your way to the bottom of.
Look at the beauty of underwater life, then eat it. Endo Sushi is supposed to be the finest in Osaka. Mr. Endo himself has maintained the restaurant since he was a young man and I believe the generations before him did so as well. Endo Sushi has been around for over a century, established in 1907.