Most Helpful Girl
I think you need to get your priorities in order... if you are so hell-bent on just getting sex out of a "relationship" then you are going to end up hurting a lot of girls even though you said you don't like hurting girls.
Most Helpful Guy
Step 1: change your mindset on sex. Stop viewing it as something you take from her and start looking it as something you share together.
Step 2: if step 1 is done, then know that any girl who you have sex with you is going to have lots of funny and be lucky they decided to have sex with you.
Step 3: don't be creepy about being sexually attracted to a girl.
Step 4: be honest about your intentions and the words will come. You don't need lines