Oni no Ou to Chigire - Chapter 2 Pg 61

Tokimori grasped the hilt of a short sword between his obi with shaky hands, and pulled it out from its scabbard. The name of the short sword loaned to him for the contract ritual was Chiyomaru, the Thousand Generation Blade. Also called the Blood Bestowing Blade, it was a special sword that could draw blood from demons that could not be cut by normal blades. It was a short sword, but to Tokimori who was a child, it was big and heavy. He was afraid to cut Yatos arm that was no wider than his own pinky with it. If he applied the wrong amount of pressure, he could seriously injure him. Perhaps sensing he couldnt leave it to Tokimori, Yato grazed his own arm against Chiyomarus blade. A line smoothly ran cross his arm, and red blood flowed. Yato pressed the opening of the wound against the shocked Tokimoris mouth. He immediately tried to turn his face away, but he remembered what he was supposed to do. He hesitantly stuck his tongue out and licked the blood.

Suck on it more. Dont let it spill.

He heard Yatos faint voice that was like sigh. He sucked on the wound like he was told, and a large amount of blood that he couldnt imagine coming from someone Yatos size filled his mouth. Resisting the urge to gag, Tokimori shut his eyes tight, and drank it down little by little. Yatos blood was smooth, sweet, and could actually be classified as tasty, but the act of drinking blood physiologically disgusted him.