~ I think Joran got Stephany to accompany him to his hotel room by saying he needed to pick something up (like cash), "it would only take a minute", etc., and that she expected they would soon be returning to the gaming tables at the casino.
~ I think Stephany went with him because 1). she believed him, and 2). she didn't want to hurt his feelings.
~ While they were in the lobby, she may have been getting a strange feeling that she shouldn't go up to his room- but again, she practiced a common trait with female crime victims everywhere... she didn't want to hurt his feelings.
~ Once in the room, Joran most likely tried to stall in someway, and then finally tried to 'make a move' on her, approaching her sexually.
~ Stephany, not interested in Joran sexually, rebuffed him, and when he started becoming more forceful, she walked towards the door of the hotel room to leave.
~ As she reached for the door knob, he grabbed the tennis racket, and swung hard at the back of her head/ neck.
~ Stunned and in pain, she fell to the ground, and he was on top of her. At this point he was overcome with rage at being rejected, and fear that she would scream loudly and bring others in the hotel to the room.
~ So as she struggled beneath him on the floor of the hotel room, he beat her, landing blow after blow on her face and head. He may have become very aroused by the violence, and may have attempted to pull her pants off at this point. Now, it was as much to do with control, as with sex.
~ She fought for her life, but was completely overpowered by his size, weight, strength, and fury.
~ As the struggle went on, he completely lost control of his actions, reached for the tennis racket, and in a blind rage, beat her to the death.
Stephany's rejection angered and humiliated him. He not only had thought he was going to 'get lucky/ get laid', he had also been hoping to get her to share or give her money to him.
There was no way he was going to let her leave his hotel room without getting one or the other.