Basilisk: The Kouga Ninja Scrolls/Tear Jerker

In Basilisk, the end of the "fight" between Oboro and Gennosuke, specially when she stabs herself to die with honor after seeing she won't be able to kill him, for not only she loved him but their duel was unfair and completely manipulated by external forces had this editor crying for hours.
Hotarubi's death was as sad as this one as well. I bawled when she, almost dead out of blood loss coming from having both of her arms cut off and being stabbed in the chest, weakly calls out to her dead husband Yashamaru with her last bits of strength, so her own murderer doesn't have the heart to say he's not Yashamaru so he just nods and lets her die in peace..
On the same note, this troper found Yashamaru's death quite saddening as well, especially after he dies after spending several episodes promising to himself that he would get back safely to his wife, the abovementioned Hotarubi. Needless to say, this troper found his killers' deaths quite satisfying, especially when one of the two murderers was stabbed to death by mere non-ninja mooks.
And it may generally come in behind all these, but Koshirou's death in the manga really got to me, along with Akeginu's undignified and miserable end.
I wonder how I could forget the scene in the last episode where Oboro imagines how her wedding would have gone through, if only things didn't go as... wrong as they did.
Actually, every single damn death in the whole anime was sad in a sort of way. If not because of the actual character, then for the clan. Inside the clan, all of them were likable characters and kind of a family. And just with the death of one family member, it will never be like before. For this troper, Akeginu's death was the saddest moment. She was so close to avenging Jingorou and Koshirou, but is stopped by Saemon/Tenzen, whom she believed to be at her side, gets stabbed with a blade, told that she would go to hell and Oboro would soon follow, then she is thrown down a bridge. What a disturbing and sad end. Thinking of the events of Basilisk as a whole, I can only think "What a Senseless Waste of Human Life". Damn shogun.
Let's not forget the gruesome yet heartbreaking way Okoi died at the hands of Nenki and how her last moments with her brother were. Just when you thought she was about to get away, especially avoiding rape twice! And then we have Saemon-as-Yashamaru as the recipient of her Famous Last Words, unable to grieve and mourn for his beloved sister no matter how his heart is breaking right there.
- As for Yashamaru, he died a man and his supposed "murderers" were comrades helping each other, and Gyobu didn't necessarily plan to kill him either.
And if we go to something else than deaths, seeing in the anime how Kasumi Gyoubu became the ruthless Bare-Fisted Monk we know... Damn, it hurt. Poor child Gyoubu and his Disappeared Dad. Damn it.
Jingoro's death is part this, part High Octane Nightmare Fuel. Seeing him melting in the ocean while he desperatly calls for help (which Akeginu was about to give to him) gives both chills and sadness.