He is free from gender prejudice, and this is very well shown in the manga. The 2 people he has the most contact with are 2 women. For a Smoker, women and men are equal, he is not ashamed to spend time with a woman, and he absolutely does not care what others think about him. He's much softer than you all think. + That's why I head canon him as a pansexual.
That explains the dynamics between the two.
She's much younger than him