"Uuurrghh..." A man groaned into a handful of flowers. Blinking, he frowned at the yellow covering his sight before slowly pushing himself up. Pale blue eyes looked around in confusion.

He was sitting on a patch of golden flowers, also the only patch of sunlight in the area. Surrounding him are large cavernous walls, and looking up, he saw a hole of light where he assumed he fell down. Alex's frown deepened. While he's not surprised that a fall that high didn't kill him, as he's been through worse, the fact that he had lost consciousness for whatever reason was a bit concerning.

Not to mention, he didn't remember how he got here in the first place. His low biomass levels tell him that he must've been in a fight that incapacitated him. And somehow he ended up here.

Growling in frustration, he got up. Memory loss reminded him of when he was first technically 'born'. Confused, weak, and afraid as he stumbled around with guns and helicopters on his ass. He did still managed to fend them off though, jumping above walls, running up buildings, throwing projectiles at helicopters...

Not bad for a "newborn."

Well, if whoever put him here expected him to as confused, weak, and afraid as he was then, they got another thing coming.

... Okay, maybe he IS confused.

"You're new to the Underground, aren't cha?"

There's a talking flower in front of him.

He repeat.

There is. A talking. Flower. In front. Of him.

What the hell.

Suddenly, he felt a pressure originating in his chest, as if someone was trying to bring something out, but it faded away and Flowey was looking at him dumbstruck.

"You don't...have a soul?"

Alex Mercer, man-made and man-eating virus extraordinaire, raised an eyebrow. He scoffed, "Souls don't exist. And if they do, then I don't have one."

Flowey spluttered, petals swaying with the movements of his head, "What kind of human has no soul?!"

"I'm not human." He said flatly.

Alex strode behind the anthropomorphic female goat who introduced herself as Toriel. He had heard her arrive when Flowey was busy staring at him like the flower's brain had blue screened (do sentient flowers even have brains?), and the flower then dug underground the moment he saw the goat.

At this point, Alex was half convinced he was in a hallucination, as much as a sentient virus can hallucinate. The question is, how? Did Blackwatch capture him and this is a new type of gas? A gas designed to lock his mental functions away while they conducted experiments on his body?

He narrowed his eyes. But his surroundings seemed too clear for that.

Currently, Toriel is his only source of somewhat non-hostile connection in this place called Underground, so she's safe from being consumed for now. Maybe if he comes across another one of those frog monsters. He needed to replenish his biomass, and the information gained would be quite helpful.

Also... his sister will be upset if she finds out that he hurt someone who wanted to help him.

Black and red tentacles made up of fleshy tendrils emerged from his back and dug into the monster's flesh ruthlessly. The froggit barely managed a weak croak of pain and terror as the virus sought to infect its flesh.

But then it dissolved into dust.

Energy flowed into Alex's being, but no memories came, and his biomass remained as it was.

"... The hell?"

"Please, mister. If you continue on from here...they... King Asgore, will kill you!" Toriel pleaded as she stood in front of the way out of the Ruins.

"I doubt it, lady."

She looked pained as she closed her eyes. "Then I have no choice. Prove to me, prove to me you are strong enough to survive!" Eyes snapping open, flames ignited from her hands, washing her determined expression with yellow light.

He felt that pressure from his chest again, but again it faded.

"You... You have no soul."

Alex tilted his head, an inhuman gesture of a predator considering its prey, cold blue eyes flashing. "Yes."

Fire puttered out as the boss monster took a step back, unnerved. "You are not human, are you?"

He smiled grimly. "No, I'm not."

Toriel let him go after that, eyes resigned. The Ruins must've been really lonely for her to feel disappointed that a viral abomination like Alex was leaving. Alex appreciated her concern, but he must get back to Dana.

"Come out. I know you're there."

Chuckling from the direction where Alex was glaring into the forest outside the Ruins. Even if monsters seem to be made from something different from flesh and bone, they still have a higher temperature from their surroundings, so he was able to pick out the one watching him with his thermal vision.

Then the monster appeared out of thin air in front of him, and Alex almost took a step back.

Okay. Teleportation.

It was a skeleton. Alex made an effort not to react in any way, even though the scientists in the back of his head was screaming at the impossibility of it. Well, all the voices, not just the scientists, are screaming at the impossibility of what was standing in front of him.

Consuming for information was out, he only got a mild energy boost at each kill and nothing else, and even that was temporary, so Alex figured he'll have to get information by talking to the inhabitants.

Sans, the teleporting skeleton, was able to determine that he wasn't human. After telling the virus that his job was to capture humans so he didn't have to fight Alex, the skeleton decided to show him around the place. The wary and confused glances sent his way was a bit annoying though. Alex haven't even killed anyone in front of the skeleton, so he had no idea what he was wary for.

Sans had asked him if Alex was a type of monster that just looked human.

Alex's reply was, "You could say that."

The virus stared at the plate of spaghetti in front of him. According to Papyrus, it was a "WELCOME TO THE UNDERGROUND, FELLOW MONSTER! NYEH HEH HEH!" present. Alex really should get going, but the tall skeleton is staring at him like an eager puppy and Sans is somehow managing to look like he was raising an eyebrow.

He sighed, and released a feeder tendril, ignoring the sounds of surprise the two monsters made. Damn, he'd gotten soft.

As expected, it dissolved into energy once he covered it with biomass. Papyrus' eyes sparkled at him.

Alex stared at him blankly for a second, before realizing that the skeleton was waiting for a compliment. He didn't really taste food with his feeder tendrils, it's why he didn't mind consuming infected, but if it will get them out of his hair...

"It's...good." Alex made an honest effort to smile, though he suspected it looked more psychotic than anything.

Papyrus didn't seem to mind though, and Sans was smiling happily.

Alex went through Snowdin Town with no trouble, it seems that most monsters didn't even know what humans looked liked. Thus, he didn't have to deal with them attacking to get his nonexistent soul.

The ones that weren't in Snowdin still used magic bullet patterns as a greeting though, which Alex learned from the Library was a monster tradition. But Alex simply had to dodge and tell them that no, he's not interested in 'greeting' back and go away or else get dusted.

Death glares seem to be effective in making them slink away in fear.

"Hoi! I'm Temmie!"

Nope.

Huh, this female knight actually recognized humans. Too bad Alex isn't one. He helpfully informed her of this, but she just got enraged.

"DON'T LIE TO ME!"

After yet another attempt to what he figured is exposing his soul in a FIGHT like what Toriel talked about, the knight was befuddled and actually listened to him.

"You're not human, but you look like them and came from the surface, right?" The fish monster asked. She had removed her helmet after Alex proved his inhumannes, revealing blue skin and fins at each side of her head. At Alex's "yes", a large grin spread on her face.

"So is it true that people in the Surface fight with giant kickass robots and have fights with giant swords and beams of friendship!?"

The virus frowned. What a strange question...

Alex thought of tanks, of helicopters, and jets. He thought of nuclear bombs that isn't quite a "beam of friendship" but still makes a huge explosion. He answered her question in an affirmative. As for the giant swords...

His arm writhed, unfurling into an eldritch mass of black tendrils and goop, and it reshaped into a huge blade almost as long as he was tall.

"While I'm not human, does this count?"

Needless to say, Undyne was estastic.

He eyed the building with the word LAB above the entrance with distaste, before looking at the pair of knights guarding a different path.

"Where does this lead to? Can I reach the castle that way?" His question sounded more like a demand in his near emotionless voice.

"The elevator is through here, and yes you can," The one on the right answered. "The King's castle is through Hotland, and past the Core. What is your business with the King?"

Alex didn't answer, but his scowl deepened. A lab or an elevator. Both having unpleasant memories connected to them. Growling, he looked up and saw the different floors.

Jump it is.

Alex quickly got through Hotland and the Core in record time, making craters on the floor and kicking down locked metal doors along the way ("Hey! That will take a long time to fix you know!" cried a small rodent monster with a yellow hat) until he reached the King's castle. There was an elevator, but he ignored it and went the long way instead.

The king was humming in the throne room, and when Alex stepped inside he saw that the monster was watering flowers. An odd sight for a king, especially for one who Toriel painted as some heartless killer. Speaking of, he looked like a male bearded version of Toriel, they must've been the same species.

The humming paused when the king noticed the virus' presence, and said, "Oh, hang on. Just let me finish watering these flowers."

Alex rolled his shoulders casually and strode right past the boss monster. "No need. I'll just be going."

"W-wait." Asgore dropped the can, a bit startled. "Where are you going?"

"Out of here."

The king followed after him, "I'm sorry sir, but seven souls are needed to break the barrier! No matter how strong a monster you are, you can't break it by yourself. How about we have some tea instead?"

Alex paid him no mind and found himself in a room of white. There seems to be waves of white going to the end of the room, where it fades before another wave started from behind him. He went deeper in and raised a hand to air, only for a force to resist him.

He backed up.

"Sir–"

And he hit the barrier at great speed, his fists having increased in mass and size for optimal smashing capability. It resisted for a few seconds, but Alex can feel it start to give in. It burned and crackled in white electricity, but he quickly healed with his biomass even as it is burned.

Then he was through.

Asgore gaped and spluttered. "Whu-bu-how?!"

Alex eyed the still unbroken (and crackling) barrier with a frown, then turned around without a word and walked away.

He paused. "Thanks for the...hospitality, I guess." His sister was always on his case about being more sociable.

Extra:

Undyne panted as she supported herself with a spear, but she was grinning widely.

"Hey punk, if you do manage to get through the barrier, maybe you can visit every now and then! Then we'll spar! And you can bring more anime!"

Alex, who wasn't even winded after kicking her ass, blinked at her unsurely. "... Sure?"

And Dana said he can't make friends through fighting people. Shows what she knows.

Extra:

"Alex-! Jesus Christ, where have you been?!"

"..."

"...Alex?"

"I woke up in an underground society of monsters that apparently have been forgotten in history, after humans sealed the monsters under a mountain with a magical barrier made by five wizards. Reality there seems to have taken a bit of game or RPG-like elements, which probably was from the high concentration of magical energy from such a small space. I've met a husband and wife that are anthropomorphic goats, a talking flower, two living skeletons-literally, a reverse mermaid that likes to fight with glowing spears, and a bunch more. Magic exists, monsters are made out of magic, their food is made out of magic, and they sometimes greet each other through magical bullet patterns. Also they can bring out your soul in a fight, which I don't have so that was something."

"...you're not the joking type."

"No, I'm not."

"..."

This is just crack, but the main idea of the barrier that got me into writing this was that there two ways the Barrier acts as a, well, barrier. Magical and Physical.

The magical aspect doesn't work on Alex, basically not noticing him, because he has no soul in this one and no magic. The physical aspect he can brute force through. Others get toasted if they do the same, but Alex can just heal.

Also, I'm wondering whether the barrier stops non-living microscopic organisms.

Also also, I've thought of Flowey getting interested on this new toy that ended up in the Underground, and keeps resetting to find different ways to mess with Alex. But this was supposed to be a one-shot and that will probably make it too long.