Here is the blurb from Wikipedia:
InuYasha (犬夜叉), also known as InuYasha, a Feudal Fairy Tale (戦国御伽草子 犬夜叉, Sengoku Otogizōshi InuYasha), is a Japanese manga series written and illustrated by Rumiko Takahashi. The series was adapted into anime and follows Kagome Higurashi, a teenager from Tokyo, who is transported back in time to the Sengoku period, where she meets the half demon, InuYasha. When a centipede demon from that era tries to take the magical Jewel of Four Souls embodied in Kagome, she accidentally splits the Jewel into various shards, which are dispersed across Japan. InuYasha and Kagome start travelling to recover it, gaining allies and enemies throughout the journey.
Anyway, I think if I were a teenage girl I would totally be in love with InuYasha. What's not to like really? He's protective. He growls. He has cute dog ears. Adorable. My son is lucky I didn't watch this series when I was pregnant with him or he would be in need of a nickname: Yasha or Inu.
And what's up with the love triangle between Kikyo and Kagome? I really wanted Kagome to punch Inyasha in the face whenever he puts Kikyo before her (okay, I don't really condone violence in the real world, but I get a kick everytime Kagome yells, "Osuwari!" )
Rumiko Takahashi does a wonderful job of making his each of his characters flawed, yet loveable because of those flaws.