Theory

After the battle with the infected, Dean's mind was fatigued. He wanted to rest but he had things he had to do. He walked over to the infected woman gripping his knife that he took at of his pocket. The knife was a kitchen knife that was hung in the utensil aisle. The knife wasn't the sharpest as most supermarket utensils sold poor and dull "weapons" which forced Dean to only use the pointed edge to stab and couldn't slice. This was also the main reason why he didn't use it in his battle as well as the short range.

He was reluctant to have blood splattered on him in case he became infected but looking at the body he saw a newly wrapped bandage on her leg. The blood that splatted from the other infected man's arm must have entered from that injury.

Dean went to look for gloves and something to cover himself with, he was going to do something really messy afterall.

Walking back to the dead bodies he was now wearing a black garbage bag and rubber kitchen gloves over his clothes. People looked at him weirdly coming back wearing that weird outfit. His cool looking face made him look goofy with those clothes. But when they thought about what that man had done just moments ago they felt like throwing up.

"Harris come wear this"

Harris looked at the garbage bag reluctantly.

"Do I have to? I don't want people to look at me funny"

"If you want blood and guts on your clothes, sure you don't have to"

"What do you mean?"

"I want to investigate the dead bodies, I also need a helper to assist me. Everyone else looks like they're on the brink of fainting. Only you look somewhat well off"

Harris looked around at the surrounding people and their pale faces. He didn't want to disagree with what this man was going to do, this was already the second time that he had saved everyone. The first was when he rushed toward the group of infected outside the building and closed the doors facing the danger himself, now he had even rushed to an infected before it was able to spread carnage inside the building with them. Although Harris didn't think with his brain often he had a knack with knowing reliable people and his feelings were telling him that this man was someone to be friendly with.

Dean took the knife and stabbed it into the skull of the infected woman. He had trouble making a big enough hole with the slightly blunt knife so he had to start hacking with more force. To the people in the crowd he was crazy, he looked like a serial killer desecrating an already dead person. More people began to leave and find somewhere to quietly throw up. Some people wanted to stop him but they weren't brave enough to go tell him to stop.

"Harris, here hold this"

Harris put out his big hands when Dean pulled something out of the head and was placing it on his hand. He was repulsed by the sight but didn't stop Dean. Looking at the bizarre brain Dean was sure that something weird was happening.

The brain was black instead of a fleshy pink colour. Dean wasn't quite sure if it was because it was burnt alongside the body of the infected so to make sure he went to the other man's corpse and took out its brain as well. He placed both in the palms of Harris's bear-like hands.

The infected woman's brain was black, there were still some places with brain matter that had a lighter hue but not what was considered a normal brain. He compared it to the man's brain noticing that a similar dark colour of the womans started to appear where the brain stem was. The dark colour must've been a common trait to infected as it started spreading from the bottom of the brain closest to the body's nervous system.

Dean wasn't that shocked to notice that it wasn't the same as a normal brain. He was already thinking of some theories as to what was happening. Using his otaku knowledge from movies, games and anime about zombies he could come to an answer rather quickly.

"Excuse me"

A man in a business suit walked and asked Dean.

"Do you know what those things are? You better have a good reason to cut out the brain of a corpse"

Dean looked at the man thinking he was stupid. He had noticed that the man's tone sounded like he was above Dean. Dean looked beside the man and noticed the man was leading a small group, he could even see the fat man who pushed the old lady outside slightly behind him. Dean didn't show it on his face but he was frowning inside. The man was staring at him pressuring Dean to talk with his numbers.

Dean was no means stupid, his grades were good in school before he stopped going and his cunning was well devolved being scammed in his early days of online gaming.

Harris saw that Dean wasn't talking to the group and was unsure of what he should do. He was still holding the two brains and didn't think he should put it down before Dean finishes examining it.

"Dean why don't you explain everything to everyone, we're all stuck inside here and I think it's a good idea for everyone to know what those are"

Dean had no reason to explain what he found. He would explain it to Harris and his group since he liked their trustworthy and simple characters. This man infront of him was sly. He showed up when Dean had finished his investigations and was trying to force Dean to share his findings with numbers. The man was basically benefiting while not suffering any damage. Even if Dean didn't have a good enough reason, the man would probably have tried to make Dean the enemy of all the other people and ostracize him by saying he had mutilated a corpse for no reason.

"Fine"

Dean agreed to Harris's suggestion. He started to share his thoughts while taking off his bloody gloves and garbage bag. He had even turned his back to tell Harris what to do with the brain. The man in the suit showed displeasure when he realised Dean wasn't showing any respect to him. Dean felt that annoyed gaze from the man but didn't care and continued to clean his hands and disinfect himself with wipes.

"As you can see, that woman was a zombie. The people outside are also zombies. They probably bite people to infect them through their saliva but this woman wasn't bitten"

"You say you have to be bitten to be infected, but she wasn't bitten?"

Sang-Woo, the man who wore the business suit asked Dean.

"On her leg there was a cut, she was sprayed with blood from the infected man who had lost his arm"

Dean wanted to continue explaining when Sang-Woo interrupted him.

"But she was fine. Everyone who was attacked by a zombie soon turned shortly after being bitten. We even had people stay in groups to make sure they could stop anyone who suddenly started attacking"

"And where were they bitten?"

Dean grew irritated that he kept on getting interrupted, he had unconsciously risen his voice.

Sang-Woo gave a questioning look to Dean and told him that he wouldn't interrupt anymore.

"Everyone who turned quickly were bitten around their necks"

Dean continued explaining his findings and proposed a theory.

"Looking at the brains of the zombies, you would be able to see a dark colour start to spread starting from the brain stem"

Pointing at the brain that was now in a jar, Dean continued talking.

"That woman was infected starting from her leg, which is further away from the brain. This was also why she didn't turn right away"

The group of people started to understand how severe his findings were. People would now have to watch out to avoid getting blood in their wounds as well as avoid being bitten.

"The brain is also the weak spot. When I was attacking its body, it didn't slow down or grimace in pain although its major burn marks. I think that they are afflicted with a virus that primarily inhabits the brain. I'm not a scientist so I can't be sure but this woman's brain is completely black and was able to move, while the man's brain was starting to turn black but hadn't moved yet"

Some people had noticed how Dean started to refer to the woman as "it", when a lady from the crowd abruptly spoke.

"How can you call her as "it", she's also a human"

""Was", now she's just something that would kill anything that moves"

The lady was taken aback with his words. She had clearly remembered being chased by people outside and seeing the gorey scene. She had no way to refute Dean's way of thinking. If anything most of the people were silently agreeing with his way of thinking. No one was stupid enough to think that those things outside wouldn't attack them if they still treated them as humans.

In movies sometimes they would still have an ounce of humanity but this was real life and no one would bet their own life on something they saw on TV.

Dean walked past Sang-Woo and his group carrying two jars with a brain inside. Now that he had given reasonable information to them he had no reason to stay. Sang-Woo would also have no way to stop him. Harris followed after Dean holding the young girl that had screamed earlier, she was sleeping in his arms.