Since you added video games to the list you might as well add Mario and Peach. Why else would she always keep finding away t to get kidnapped? Bowser secretly runs a shelter for battered women, and as Mario you have always been searching the world over to find where he is keeping her so you can bring her back home and teach her the errors of her way.
One thing I never quite got about Inuyasha. How could Kagome be the ancestor of Kikiyo when neither Kikyo nor her sister Kaede had children? I actually thought that it might make a good 3 Minute Expert to talk about the differences between US and Japanese Valentine's Day, but it seemed a bit too late for such a suggestion.
So far, I have realized that love relationships in anime are a little bit hysterical, with lots of violence (physical and psychological) and often with fits of (sometimes unnecesary) insane jealousy; pure gold for shrinks and psychologists (yes, tsundere girlfriends, I'm looking at all of you).
It would be nice to explain the differences between American and Japanese Valentine's Day, as FoxxFireArt mentioned before.