The high to them can even be like sex itself. They'll lose their whole world just for this drug, and in the song the drug is talking to the person basically trying to convince them to fall in love with them. Just like any other human being heroin can make someone weak on their knees for them. It can also lie just as well as a person can, but instead of telling them, it shows them that everything is going to be fine. Just inject a little bit inside of me and all of your problems will go away. Then when you least expect it, that drug is all you want in life. That's all what is on your mind, when you think of it you get all happy inside. It's equivalent to love, actually it is love. The needle going inside of your skin, and the heroin getting injected into it, can be just as satisfying to a person then a penis going inside a woman or a man. A person who is addicted to sex, and a person who is addicted to drugs are basically the same thing.