THERE WILL BE SPOILERS ABOUT THEIR DEATHS IF THEY HAVE DIED..
This is my opinion, so if yours is different, good for you.
Okay, coming in at #10 is... Oscar.
A lot of people may not remember Oscar, or care about him, but I really liked his character. He was apart of the 5 prisoners that survived for 10 months in a cafeteria inside the prison (Axel, Oscar, Tomas, Big Tiny, Andrew). Rick agreed to clear their out a cell block for them as long as he never saw them outside or near his people. While the prisoners helped clear out a hallway, Big Tiny gets scratched and insists he can keep fighting, but Tomas hits him upside the head with a crowbar and bashed his face in. Then, while clearing another hallway, Tomas intentionally throws a walker on Rick, stating it was "coming right for him", Rick says "I get it, shit happens." Then puts a machete through his skull. After, he chased Andrew into a court of Walkers, he locked him out there. When Rick comes back, he asked Axel and Oscar if they knew anything about that, and Axel begged Rick not to kill him, when Rick turned to Oscar and asked him, he responded, and I love this line "I ain't never pleaded for my life, and I ain't about to start now.... So you do what you gotta do." He proved his worth when he saved Rick's life by shooting Andrew, and then volunteered to go save Glenn and Maggie without hesitation. He was killed when shot in the side, helping lift Glenn over the buses that guarded Wood-bury.. He was shot in the head out of mercy, by Maggie, to prevent Reanimation.
Don't worry to everyone thinking "what the fuck is Oscar doing on this list", he is the only "Non-popular" character in this Top 10.