for the ultimate most pleasureable experience, girl on top is!
for a start, she can tease you by gliding at the entrance for a while.. and gradually sliding in as the heat builds up and it becomes more slippery.
girl's physiology are like electric irons, they heat up slowly. when they are on top, they are in control of that heat.. and they decide when it is hot enough to get it all in.
ma move gyud ni sa mature section bah...