Definitely not. Nor is it "evidence" of bisexuality etc.
But you can imagine her lawyer thinks it's relevant - important to get across as the Pros/experienced cops have judged this to be a murder with a sexual motive.
Let's see if Sh backs up NM's testimony that she would also spot the pretty teens for him, in a jokey way.
Speculating in her shoes - ie. Not sure I would want to be "feeding" my OH's peccadilloes/fetish if I personally found that peccadillo distasteful and he wanted me to engage in it the following week.