I don't know about you, but I was really excited when I heard about Rogue One. I was sad that all the characters died, but the death that effected me the most was K-2SO. I love K-2SO. He is the first truly humanoid robot I have ever seen in a movie, and I immediately took a liking to him. I mean, a sarcastic, hilarious, rebel robot. . . how can you NOT like him?
I love sarcasm. One of my favorite lines of K's is "I find that answer vague and unconvincing." I do use that, by the way.
I know I'm not the only one who is wounded by K's death: how recently have you seen Rogue One? Well, do you remember Cassian's face after K died? SO HEARTBREAKING. Well, for me at least. I mean, I cry during Harry Potter and the Deathly Hallows (part 1) upon seeing Draco's face after Voldemort (sorry, You-Know-Who) kills Charity Burbage. . .
May the Force be with you.