Artifact of Attraction: The Shikon Jewel, which not only grants wishes, but increases a being's powers and abilities.
Humans Are Bastards: When discussing the repercussions of the Shikon Jewel's return, Keade makes a point of saying that along with swarms of demons coming after it, there will be many humans who are even worse.
Nausea Fuel: Everything involving the carrion-crow. The thing took over the body of a bandit lord and used his underlings to get the Shikon Jewel.
Inuyasha: Carrion-crows don't fight on their own when there's dead bodies handy. They ain't so tough, but they're hella' nasty!
Never Be Hurt Again: Those who have watched at least the first season through know this is a big part of Inuyasha's hostility towards Kagome.
Nice Job Breaking It, Hero: Kagome shoots down the Carrion-crow carrying the Shikon Jewel. Unfortunately, she finds out her aim is too good. She picks up and shows Inuyasha a suspicions looking jewel, thus beginning this long adventure.
Oh, Crap!: Inuyasha when Kagome presents him with a shard of the Shikon Jewel.
Kagome: Could this be…?
Inuyasha: "Could this be"… what?
Kagome: (picks up the fragment) A fragment of the Sacred Jewel…?