Within Michelle's body, Nyxaroth could see what was going on.
The Life Stone was forming a contract with Michelle. If that was the case, it would have formed it with the blood it had to push through to come out of Michelle's forehead. But it didn't react to that blood.
Nyxaroth couldn't exactly tell why the Life Stone ignored that blood, but he could guess. It had been joined together from parts within that blood, so it didn't even take it as a potential material to use. But when it peeked out from under Michelle's skin, and new blood touched it, it started sucking it in.
As for what it wanted the blood for, it was aligning itself with Michelle's spirit energy, which was flowing through her blood. It was basically becoming a part of her.
After sucking in the blood from her finger, the Life Stone let it leave and join the blood around it, so even after a long time of having her blood sucked, Michelle didn't feel dizzy. She wasn't losing blood.
