Well, it might make you feel so good for another reason other than eroticism...
There are 3 symbols in this dream: a midget, sex and a hole in the neck. The midget might indicate you may have had feelings of littleness, insignificance... Meanwhile the neck is the body part that connects the mind/reason/the brain to the body where the heart is. Thus a hole or an injury in the neck would indicate a separation between your mind and heart, either because of the feelings of insignificance or causing that feeling. Sex is an act where you unify two opposites: so the midget having sex in the hole in your neck symbolizes unification of your mind with your heart again. And sure, that would make you feel much better than you felt before it.
