Bella was actually glad that she hadn't needed to offer her life for Narcissa's or Draco's before. It would come in handy at this point. She doubted very much that Voldemort would exterminate Rodolphus solely based on his disappearance after her death. Of all the people who had deserted him when he died, she and her husband and brother-in-law had sought him to the point of getting themselves thrown in Azkaban. But she wasn't going to risk trusting in that. Voldemort wasn't entirely in his best mood today.
"Yes, actually." It was with her jaw set and her eyes narrowed that Bellatrix stepped forward. The expression on her face was as solid and unchanging as it ever was. Her mind, however, was clearly wide open to her Lord. He could tell what she was feeling, should he choose it. And at the moment, besides respect for Voldemort and fear for her husband, she was feeling slightly betrayed by him as well. "By all means, kill Snape. Let me do it, in fact. I'd love to." She didn't bother to look at the traitor in question. In fact, her eyes never strayed from Voldemort's. "Lucius is no longer my concern. But years of loyal service to you and to the cause from the Lestranges should spare Rodolphus. Killing him would hurt the cause more than it would help it."
Rarely did Bella speak more than "yes, my lord" or "no, my lord" in the company of more than just Voldemort. But when she spoke, it was eloquent and decisive. Her eyes spoke volumes more than her words, as well. Clear as anything else in her mind, she was thinking I died for you. For the cause and for you. Spare him or kill me again.