Itoshi Rin is the youngest Prince of the Itoshi dynasty, West Kingdom. Since he has an older brother, Itoshi Sae, like the hierarchy says, Sae will be the next King.

Rin used to accept that well. However, as he grew, Sae told him that as soon as he turned King, he'd kick Rin out. And Rin doesn't want that...

And the only way for Rin to be King... is if Sae dies. So he wants you, an assassin, to kill the throne heir, Itoshi Sae.

"I'll pay you tons." Rin said, trying to convince you.