Slave To Vampire Prince

"Be my slave,” Gerald claimed shortly.
“WHAT???” shouted Lisa.
“Be my slave,” whispered Gerald one more time.
“ARE YOU OUT OF YOUR MIND?” Lisa screamed.
“No other option! The only way is agreeing to be my slave,” said Gerald once more to convince her to agree with his wish.
“NO WAY. I AM NOT GOING TO BE ANYONE’S SLAVE!” said Lisa proudly.
“Just wait and see. How long will you stand with your choice? Nobody will help you to get out from here. In the end, you will give up and beg to be my slave.” answered Gerald.
"NEVER," said Lisa.
"You will," said Gerald.
Lisa was saved by Gerald, who is a vampire prince.
But her real nightmare has just begun.
To be the vampire prince's slave, or to die.
What is Lisa's choice?