" Mikhail sought Raven’s mind, crawled to her with warmth and love, his arms a shelter. The needle jabbed the inside of his arm, pierced hers. He had no doubt that his brother would monitor the transfusion closely, making certain Mikhail was replenished with ancient Carpathian blood when needed. Jacques held Mikhail’s life along with Raven’s in his hands. If she died, Mikhail followed her--that was an indisputable fact. He could not afford to remain alive if he lost her. He knew in his heart, that the black fury that remained would endanger anyone near him, Carpathian and human alike. He could only hope that Gregori was up to the job of dispatching Carpathian justice to him swiftly and accurately should Raven die. The last thing he wanted was to choose to give up his soul.
No. Even in an unconscious state, Raven was trying to save him.
He stroked her hair in long caresses. Sleep, little one. You are in need of healing sleep. Using his mind, he breathed for both of them, in and out, forcing oxygen into his lungs, her lungs. He kept the rhythm of their hearts together. He took on as much of the mechanics of her body as he could to enable her to heal.
Jacques knew Mikhail had no real choice. He could not live without his lifemate and remain Carpathian; he would succumb to the darkness that lived in all of them. Right now Mikhail was using his power to keep her blood flowing, her heart pumping, and her lungs working. It was a draining process. "

― Christine Feehan , Dark Prince (Dark, #1)