I have plan to go to hongkong to meet my american boyfriend. What are the documents needed to bring?

My boyfriend and I have plan to tour hk for 6 days. I have no job but only my american boyfriend pay all the expenses in our stay.
What are the documents that are needed to show in immigration?
Hope you can answer my question because We have plan to travel next month and we have to book a ticket and a hotel reservation ahead. Thank you