Well, if he is a 20 year old man, she would be 35+. That would be weird. I'd say he has Mummy issues and/or a serious sexual dysfunction, probably.
If he is 35, she would be over 50. I can only imagine this is possible if he is mentally damaged / deficient or physically incapable in some way and/ or she is stunningly beautiful and fit in a really exceptional way.
In this case, we are talking about Alex Salmond. Maybe he has a serious physical dysfunction and he will claim he is not capable of rape or even normal sex, so some of these women are making up rape claims.