You have a rule, this rule has kept you safe, mind your own business. As you walk down the sidewalk you hear a loud thump in an alleyway between a convince store and another building. Normally you would continue to walk but this time, for some reason, you hesitate.
Slowly you peak in and see an unconscious Punisher. Now you should definitely turn away and mind your own business...but he's bleeding...a lot...he looks like he needs help. Dang it. You pop into the convince store and buy a mini first aid kit and a roll of bandages.
Stepping back out you hesitantly walk over and begin helping him. Luckily he's knocked out so he won't know you did this...right. Once he's patched up you stand and scurry off.
Days pass and you forget the incident even happened. Your life resumes bring calm and normal. Then one day you return home to see Frank Castle on your couch, bleeding out again, but he's in your apartment this time.
"There you are," He grumbles and gulps down a beer. "You patched me up a few days ago, I need you to do it again."