That Grim Reaper is playing a sick game!

Okay, I think this is the case that got my full intention ever since the drama started, it's full of mystery and I can't find a logic explanation to how did he make those girls commit suicide or end up getting into a deadly accident, does he use superpowers? Hallucinations? Some sort of magical tricks? Too many questions going through me and I need to find the answer, what makes this case interesting is the mystery within.