The initial accident

Mark had his hand on the steering wheel while he patiently waited for the time to come. 
He still couldn’t believe what he had to do, but it was the only option he had right now.
Just a few days ago, he drove in the same truck that he was currently inside. He made one delivery for a new client. It was the very first time he had worked with that person, but he had heard some pleasant words from others, and the payment was reasonable as well.
He needed the money, as he had two granddaughters he raised by himself. Unfortunately for him, he wasn’t old enough to retire, and a car accident had killed their parents. His wife died while giving birth to his daughter, who was the mother of the twin granddaughters, Maria and Melinda.
Driving was all that he was good at, and he had his truck, which was the third thing he was most proud of. The first and second were, of course, his granddaughters.
The person needed him to deliver some strong chemicals from their storehouse to one of their factories. The person who usually did the delivery was unavailable, and thus a friend of Mark recommended him for the job.
Mark was glad for the extra money since his granddaughters would soon go back to school, and they needed money for books, notebooks, pens, and a lot more school equipment. Along with, of course, new clothes and backpacks.
He was rather tired that day since he had no sleep because Maria, the youngest of the twins, was sick. Mark ended up staying up to staying up all night, making sure she was alright.
His eyes were heavy, but he had drunk some strong coffee to keep himself awake. But in the end, it wasn’t enough as he didn’t notice the person who had just appeared out of nowhere on the street.
All he heard was the thump of the hit, and he hit the brake.
He got outside the truck and at the back of it and saw what he was afraid of. He had hit a male who was in his early twenties and wore a simple jumpsuit. 
Mark didn’t know what to do. He had never been in an accident. He never even had a speeding or illegal parking ticket in his life before.
He couldn’t report this, as he would have to stay to wait for the police and would be late for his delivery. If he got delayed or people learned about this, they wouldn’t want to work with him again, and if the world went around, he could never work for anyone.
So he had to dispose of the body, and he had an idea of how to do that.
He had examined what was on his truck since he didn’t want to be part of anything illegal, and he had also done his investigation beforehand about what he would transfer.
He knew he could use just a little of the strong chemicals and would be able to liquify the entire body.
He brought the body inside at the back of his truck and put it inside of a big plastic barrel he had. It was something he had to put stuff to be delivered if people didn’t have a case of their own. Fortunately, he had a few of them, so he could spare one.
It was big enough to fit the entire body, leaving just a bit of his legs outside. Mark covered his mouth with some cloth and opened one barrel with the chemicals. It released some fumes, and he hoped it wouldn’t affect it due to getting opened like that.
He then used a bucket to fill the barrel, but he had to move fast as the chemicals ate up the bucket.
Even with the cloth covering his nose and mouth, some smell passed through it, and it was the worst thing he had ever smelled. He tried to move faster and held his breath.
As he seemed to have enough to fill half a barrel, he got outside the trunk to get some fresh air. Even if he didn’t fill it completely, it should be enough to take care of the whole thing in time.
After catching his breath, he went back in to put the lid over the open chemical barrel. As for the body, the process hadn't finished yet,  but it had been damaged enough for his feet to have slid in.
Mark closed that barrel too and had it strapped into the truck’s walls so that it wouldn’t move while he drove.
He couldn’t spend any more time here, and he couldn’t dispose of that container here either, thus he had to move on. He drove as fast as he could but also was careful, as he didn’t want another accident to happen.
He made it to the destination with just a few minutes’ delay, which the client didn’t mind.
He helped them get their barrels outside his truck but didn’t leave his vehicle and paid attention so that nobody inspected or tried to get his barrel. Fortunately, theirs had the company’s logo imprinted on them, so nobody paid attention to the other barrel.
After inspecting everything, the client was satisfied, and all seemed good. Mark got paid and was on his way back. He didn’t use too much of their chemical, and it wouldn’t be uncommon for some barrels to have a little less. As for the lid, it didn’t have a seal that would break when he opened it, so there was no sign that he did so.
He was in such a hurry that he forgot to give them his card in case they needed him again.
He drove as far as he could and reached a junkyard.
He was familiar with this place, as he used to work here, and actually knew the person in charge really well. He stopped at the gate since it was closed.
“Hey Mark, is that you? What are you doing here? Did you finally decide to let this old horse of yours join my collection?“ an older woman who was at the little stall at the entrance questioned.
“Still not that day, Kelly. I just had a delivery left on me at the last moment, and I have no need for it. Do you mind me disposing of it here? It is some chemicals from those big companies, so it may help melt some of your trash.“ Mark answered.
Kelly smiled at him as she pressed a button to open the gate for the truck to pass.
“Well, you know the way, honey. Try not to let them get them in the water, or if those environmental people hear about it, they will make my gears grind. And I don't enjoy this as much anymore now. “
Mark gave her a smile as he drove in and found a spot to remove what remained of the body.
The chemicals did their job well. Despite that, there was still the smell but it was covered by everything else here, except if someone got too close to smell it of course.
Mark chose a place that someone would probably not visit… at least not before the smell was gone. Then, as soon as everything was ready, he went back to his truck and started driving back home.
As he got out of the junkyard and got further and further from it, his anxiety lessened.
Then he heard a ding sound, and two panels appeared out of nowhere in front of him.
He almost lost control of his truck but managed to stop it in time and read what was on the panels.
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NEW SUBJECT ACQUIRED
Activated System: Truck-kun
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NEW TARGET ASSIGNED
Description: Overworked High School student 
Rewards: Truck Upgrade
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