(My little explanation for why nine turned into ten. Because I believe the Doctor's last thoughts would influence his regeneration.)(I don't own Doctor Who.)(Please leave a review!)
He wanted her, oh how he wanted her. And he felt his control slip further and further away every time she smiled at him, every time he grasped her hand, every time they hugged.
Every time he felt his control slipping, he forcefully reminded himself, 'she doesn't want me like that. How could she want someone with such Monkey ears?' He had to remember that he had lasted centuries, he could wait a little longer. Just until he regenerated, until he was younger looking, better looking.
Still, for all his self control, he could not stop himself from kissing the vortex out of her, although it was not completely necessary.
As he felt the regeneration energy flowing through him, after his desperate attempt at an explanation, at a goodbye, all that went through his head as he let the power take control was, 'make me sexy.'
He focused so hard on becoming sexy, he completely forgot about trying to be ginger. And although he did not end up ginger, the Doctor, in Rose's opinion, was most definitely sexy.