Well, I think It was the Jiraya's death on Naruto Shippuden anime series! He were a great teacher and very funny as well. This death was very sad, in sure, and most anime fans hade missed him a lot while the series continued... Another death also in Naruto had touched the fans a lot. Neji Hyuga's. I really aprecciate the way of some anime series are build, and how the characters develop their relations during the history goes on!