So,here's my question
Opponent Toshiro
Me dark rit (Toshiro)
Opponent Dark rit (dark rit)
Me dark rit(toshiro)
does my opponent then also pay half of his/her life and lose the toshiro, while i lose just half life?
Answer:
So your scenario is that you're Dark Ritualing his Toshiro coming into play/ card effect, he's Dark Ritualing your Dark Ritual and in response you're Dark Ritualing the Toshiro again?
When the queue resolves you would lose half your life and he would lose half his life and his Toshiro.