Lyric discussion by SummerMcLovin 

To start off with, this is from what I hear and deem to make sense. I could be wrong with some of the lyrics and their interpretations.

The first verse is about a girl who might be forced to sleep with the Principal (but hasn't done so yet) to get her required grades. The narrator offers a phone number (36-24-36, can't hear the last 4 at all) and his services, which will be to 'negotiate' her graduation. Killing the guy would not be likely to help her, as she wouldn't pass or have anyone to sleep with to get the grades.

The second verse is about a different girl who is being cheated on. It sounds like "He's double dealing" and "We'll [forget/get round] him", and with the assumption that the narrator is straight, he's offering to cheer up and/or get back at the cheating boyfriend - all in all talking to a girl.

The third, as has been said by Sonofagunzel in his brackets, is likely to give him an easy way (or "back door") out of the relationship with his nagging woman.

The narrator is obviously happy to do a number of "dirty deeds", which might include murder (through the methods mentioned) but nothing in the first three verses necessarily involve it.

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