Angelus was always so shortsighted. He didn't think things through. Of course, killing Jenny was a smart move on his hand, but Drusilla had a plan for a move that would be even wiser. But not just affecting the present, she had learnt spells of old that could let her travel to wherever and whenever she wanted.
She also knew how to revive people using the magic she had heard of. She could be absent minded, but she wasn't a bloody idiot. She also knew spells of possession. Of course, it would be difficult to fully possess someone when you still have a physical form, but to partially possess? To influence someone? That she could do, and with no bloody slayer. Especially if she stayed in a different area. She even had an idea for a fake name she could go by when possessing Jenny.
Cheryl D'Alessandro.