So far what I learned, is that many factors play into attraction. Looks are one. A big factor for me is also seeing someone as an equal. Fuck dates are fine with much younger or older ones but dating and a relationship, nop. I want to take the other one serious, I want to be in about the same stage of life experience, to have similar goals and similar pop culture references (tv shows, music, games that we played as kids). Seeing someone as an equal comes with similar age for me.