Maes Hughes from Fullmetal Alchemist.
He was a genuinely nice man and an uncorrupt, yet kickass official. He was a second father to Ed and Al, an incredibly loving father of a very young child, and Roy's best friend.
I think what made it so bad is that the death came as such a surprise, as a lucky shot in a murder. And the homunculus took the form of his beloved wife to do it.
So, not only was Roy crying silently under the brim of his hat at the funeral, but his daughter, who was either three or four and had just seen him the night before didn't understand. She stood there with her mother, asking why they were burying "Daddy," pleaded with her mother that they couldn't bury him, that he said he had work to do; she begged her mother to make them stop and her father to wake up, which prompted the stricken mother to cry.
And on top of it all, Ed and Al don't even know, which leaves us with that ghostly memory of Hughes in Ed's mind, as the train passes the station, seeing a smiling Hughes waving them goodbye.
Maes Hughes wins, hands down.