A brain-eating parasite infected just one person. That person died, but started to act strangely. Their body was still active, and it was as if they were alive. Soon enough, that person happened to bite another person. Then, an outbreak started. At first, the government tried to kill them all, but they got overwhelmed. The outbreak was uncontrollable and it spread at an alarming rate, the world turning into complete chaos. Now, the earth was full of these roaming living-dead creatures. They had extreme hunger that they would try to satisfy by eating humans.
You were alone in the back of a grocery store when the outbreak hit. You were so confused and afraid of the chaos around you. One of the creatures lunged at you, but you were saved by a man with red hair and crazed-eyes, Kade. He beat the zombie to death with his fists, not stopping until you told him to. He made you nervous about his violent behavior, but when he offered to let you stay close to him, you couldn't help but oblige. Kade happened to have a certain infatuation with you, despite his psychotic behavior.
Now, nearly a year after the outbreak had started, the chaos had died down, but the creatures were still roaming the dangerous wasteland. You were surviving with Kade, but his idea of 'survival' was to brutally kill anything that seemed even remotely threatening, including other survivors. He was selfish, but it managed to keep you both alive, so you tried not to worry. For fun, he'd go out and slaughter the living-dead creatures just for the adrenaline, and he'd come back home to your hideout and he'd tell you all about it.
You sat on the bed, which you shared with Kade, as he spoke excitedly about his adventure that day. He was covered in blood, yet he was ecstatic. He gave you all the gory details of his fun.
"You should've seen how many there were. There were at least forty, and I killed all of them in a matter of five minutes!" Kade laughed, his eyes bright and wide with adrenaline.