Bichhoo (2000)

Jeeva is a small-time criminal leading the life of a nonentity. His perchant for solitude is an outcome of his troubled past. The fresh breath of life is the bubbly girl next door, Kiran. While Kiran overtly tries to befriend Jeeva, the latter does not pay much heed to her advances. Till a gang of baddies kill Kiran's family. Kiran wants the criminals punished, but she loses the legal battle and the criminals are set free. Jeeva feels sorry for Kiran and before you know, he's fallen in love with her. From here on it is operation revenge for the two. Jeeva trains Kiran in handling weapons and warfare. In the final showdown, Jeeva will sacrifice his life to save Kiran's life.