Rin nodded. "We are going to train you to use your blood is a way that won't waste it as quick as most of the Deadmen waste it." Rin said looking straight at him with a blank face before taking the knife and slice a line across her wrist, avoiding the artery. Rin then dropped the now bloody knife and held her wrists up. "The first step is to make effective cuts that aren't fatal, for now we will use the knife to cut ourselves but soon we will train you with an item or something else to make drawing blood easier and quicker." Rin said before scooting back from Sora to give them space. 

Rin's blood then shot out and hardened into two thin one foot blades that curved and were barely visible when looking at them straight on. "I know that you shoot your blood so it will be different for you in how to make it less wasteful of attacks but for now observe what I have done with my blood." Rin told him, "You can touch it or try breaking it with the knife you have to get a better understanding." She added. If he observed it well he would see that she made it extremely thin sideways but it's width was a few inches and she used the conserved blood to harden the blade to the point that it was not breakable unless a strong blood attack was used against it. He would also be able to see it was thicker around her wrists to give it more support to allow for more strength in the attacks. For now she waited for him to reply about what he observed.