Duke is one of the people who wouldn't know anything about kissing people in black, partially because this particular month is the only time that kissing even crosses his mind, and partially because he can't see what anyone is wearing anyway.

So this is a tall blind man, leaving the library with his fingers intently moving across a page. His only reaction to her walking over is a slight tilting of his head - he hears the movement - and continuing to walk and read.