However, a person also has the right to take previous history into acount if they choose to. And whether or not they do doesn't necessarily concern you (not trying to be rude, I'm just trying to make a point)
Why? Why would it make a difference if he's never dated or if he has been with 30 people? Unless he has some kkind of disease or unresolved issue whoever he dated before you is none of your business ( not trying to attack you personally or anything pixiedust, i just don't get why something that is in the past and can't be changed should be so important as to not date them at all)
People have different qualities that they look for in a girfriend/boyfriend. Sometimes, that quality concerns relationship history/ number of partners. And to look for a certain person that has the qualities you want (even if it does concern the past) is reasonable. (Not a personal attack on you either :) )
OP assumes that having a lot of practice means the same as being an asshole. I have learned that some insecure people tend to narcissistic overcompensation in relationships btw
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