Sacrifice the lives of your loved ones.
Chloe in the black robe had obviously made a plan. If Angel wanted to silence her, he would allow Chloe in the white robe to teleport away at the cost of his own life.
Angel didn't know where they got this magical leather scroll, but he knew that he might not be able to deal with these two people today.
Because killing one person and silencing them all are completely different things.
Chapter completed!