Ace Swift. Blackmailing the competition is one thing, but using a fellow racer's young sister's life to reach that end is nothing short of disgusting. And then there are his Last Words. The way he narrates the fabricated story of how Sonata will die is absolutely creepy, especially after raging at Sonata. It's just the absolute epitome of an Asshole Victim:
Ace Swift: YOU'RE NOT GOING ANYWHERE, SONATA!
Sonata: What are you doing!?
Ace Swift: You met an unfortunate fate in the forest...
Ace Swift: A ferocious beast got to you and ended your life!
Sonata: No! Stop! Don't come any closer!
Ace Swift: I then fell into a depressed state, and couldn't race anymore. No one will notice my performance drop, because I was forced to retire... Because you died! My dear Sonata, I'm so very sorry. But I am afraid I must ask you for one more thing... Farewell, Sonata...