Medieval mentality includes not only winning the heart of your significant other, but also earning the respect and admiration from the significant other's family. Having this mindset means you see your relationship as much more than what it appears at face value. One with medieval mentality views his newly formed romantic relation of strategic importance, be it social, political, or economic. He sees his relationship as a uniting of clans, tribes, etc. in which both parties will mutually benefit.
Tampere: Dude, you have medieval mentality.
Turku: I know, it's totally awesome.