Block Heater Cord Melted

The Problem:
The electrical plug has melted rubber/plastic around the prongs from over heating. It looked like it was plugged in 1/2 way for a day. How do I clean the melted rubber off & do I need a new extension cord? The plug from the heater looks ok before the metal prong connection.


The Story:
Ok so I was being a good guy by sober driving my friends around last Saturday. When we get back to the out door parking lot everyone gets out & I go to plug in my block heater as usual. But my drunk friend pushes me away and says he'll do it. So he plugs it in & I go over to check it but he keeps pushing me away. At a glimpse in the night, it looked like the heater was plugged in fine so I left.
I just went outside today to unplug it:
- the plug was only 1/2 way in
- there were some sparks
- the extension cord (female end) looks melted
- the block heater (male connector) just has some discoloration & melted plastic on the connectors

Pretty annoyed....

 

1. Does it still work in the current state?
2. If yes...then who cares? Just reprimand your friend a little bit and always do that stuff yourself in the future.
3. If no, either clean off the plus(s) a little bit to see if that helps. Maybe check all connections. Then ask your friend nicely to get you a new one. Or do without it. I don't think it gets cold enough south of the top part of the lower 48 to actually need one.