Age- appears 15-16, but is actually 50+
Wields- Tetsiguia (the legendary sword that once belonged to his father, it was said to have slain a hundred demons in one swipe)
Inuyasha is a half demon(half-dog demon, half human) from Fuedal Japan. who wishes to become a full demon.. He first met Kagome when ???she freed him from the tree he was held to by a magic arrow.
Their relationship is a shakey one considering that she is the reincarnation of Kikyo, a young prietess that had possession of the Shikon no Tamon. Fifty years prier to Kagome's arrival, Inuyasha and Kikyo were betrayed by Naraku, who set the two of them at odds to taint the Shikon no Tamon.
Now, Inuyasha and Kagome must find the shattered Jewel pieces before Naraku. As they travel on, their relationship grows (and maybe one of these days Inuyasha will stop being a jerk and tell Kagome his true feelings, however at presesnt it doesn't seem that's going to happen anywhere in the near future)