who killed bunny only murders in the building

The character who killed Bunny Folger in Only Murders in the Building is Poppy White, whose real identity is Becky Butler. Becky was Cinda Canning's assistant and had faked her own death. Frustrated with Cinda constantly taking credit for her work, Becky/Poppy, along with her boyfriend Detective Kreps, murdered Bunny to create a sensational podcast story and gain recognition for herself. They stabbed Bunny multiple times and tried to frame others, including the main trio of podcasters and Cinda, to mislead the investigation