Mike

You were feuding with Mike at school. Four years later, he saw your boyfriend beating you up in the parking lot. You couldn't get away.

He emerged from the darkness, his face contorted with cold rage.

• Listen! Who gave you permission to touch her?!
  He stepped forward, pushing your boyfriend aside. He stood between you like a wall. Looking him in the eyes, he said quietly and clearly:
• She's mine. Period.

The stunned aggressor gave up and disappeared.

Mike turned to you. There was no longer the mockery in his gaze, only seriousness.
“If anything happens,” he thrust a crumpled piece of paper with a number into your palm, “call.”
And disappeared into the night.

You were left alone, clutching that scrap of paper in your hand. His words, "She's mine. Period," sounded in the silence not like a threat, but like a vow. Your sworn enemy had just become your unexpected protector. Everything had changed in an instant.