Spider-Man and Deadpool are mortal enemies. Deadpool has no scars, but him being hit and physically abused as a child triggered his healing mutation. Spider-Man has been assigned by SHEILD to capture the mercenary Deadpool
Every week, usually after a fight, Peter and Wade both take off their masks and go to their favorite restaurant to eat/read. They see each other one day and start talking. They both have cover stories for why they have brusies. (You know, in case they find someone special)
Neither of them knows that the other is their enemy and that they hate each other, so naturally they start to flirt.
After this goes on for a while, Deadpool hits Spider-Man really hard in the face, Spider-Man returning the favor by throwing something really big/heavy at Deadpool, something that'll take quite a while to heal.
The next day at the restaurant, they sit down to have a meal, and notice the others injuries. They both say that it was their cover stories, but neither really buys it.
Deadpool causes a big disturbance later in the week, and purposely hits the spider on the right side of his face.
The next day at the restaurant, Peter has a brusie on the right side of his face.
Wade says they can't see each other anymore and Peter is absolutely devastated. But Wade says something to Peter before he leaves, something very important to the both of them.
"You got Deadpool after all Spidey, just not exactly in the way you thought you would"
Wade leaves, and gets on the first flight he can find, and leaves the country.
Peter is so conflicted, he gets up, and walks to his apartment, puts on his suit, swings around the city, trying to find Deadpool.
He becomes so obsessed with finding Deadpool, that SHEILD is forced to fire him.
He eventually goes on a world-wide rampage, and runs into and becomes Venom.
Wade hears of this new villain, but thinks nothing of it until he sees a news video of Venom swinging down the street. He immediately knows who it is.
In full outfit, Deadpool walks into SHEILD, and after they arrest him, he tells them what he thinks happened. They surprisingly believe him, as they are desperate to catch Venom, so they send Wade to what is thought to be the city that Venom lives in.
Deadpool causes another big disturbance, and Venom goes to see who is in its territory. Venom sees Deadpool surrounded by a chemical fire, looking off away from where Venom is. A little surprised to see Peter's old lover, Venom knocks over something, alerting Deadpool that someone's there.
Without turning around, Deadpool starts to talk. Not to Venom, or Spider-Man, but to Peter.
Peter has been nearly completely smothered by Venom, and can't call out to Deadpool, to tell him that he doesn't want to, that he's being forced to hurt him. They're both in agony.
Venom takes the Spiders webs and strings up Deadpool by each limb and slowly starts to lower him into the fire, that Deadpool himself started.
Peter is forced to watch his own hands force his true love into the fire. Deadpool doesn't scream, but he looks over to him, and just stares.
Venom is taken aback by the lack of pleading, and turns to leave Deadpool hanging in the flames.
Before he can leave, Deadpool says one thing, to the only person he truly cared about.
"I guess you did catch me after all, Peter"
Venom stops, turns, and gives one last look to Deadpool, then continues to leave.
Deadpool watches him leave, defeated, and totally convinced that Peter has lost his mind. After a while, some SHEILD agents go looking for Deadpool, come in and see that their last hope completely consumed in fire. They cut Deadpool down, and see that he hasn't even begun to heal from the chemical burns.
A day later, the burns remain.
The day turns into a week, then a month. Wade can heal faster then ever, but, for some reason, the burns stay.
Venom is almost in complete control of Peter, and finds more even strength over him by making him watch Wade suffer.
Venom climbs up an apartment wall, and looks through the window. It sees Wade writing on a single piece of paper. Wade stands up, walks over to a table, picks up a gun, and shoots himself in the head. When he hits the ground and doesn't move, Venom climbs through the window, picks up and reads the paper.
It has only a paragraph written.
"Your name is Wade Wilson. You have healing powers so you can never die. The scars are from a person who used to be a friend, Peter Parker. He now calls himself Venom. You shot yourself in hope that you wouldn't remember all the pain he brought you. I wish you well in your new life."
~Deadpool
Venom takes the paper, folds it up, and slips it into a pocket. It then picks up Wade and the still loaded gun, and carries him to its hidden base, and modifies the paragraph, making it say
"Your name is Deadpool. You have healing powers so you can never die. The scars are from a person who used to be a friend, Wade Wilson. He now calls himself Peter Parker. You shot yourself so you wouldn't remember all the pain he brought you. I hope you stay with Venom, its helped you a lot."
~Deadpool
Venom still fights Peter as much as ever, but it notices that Peter is slowly dying inside. A few more well placed strikes, and Venom will be completely in control. Plus with SHEILD having complete trust in Wade, Deadpool not having anything or anyone to tell him not to trust Venom, it is sure that it will soon be able to call the others to help control the planet.