John Christie, a hysterical hypochondriac. Hated women and used his knowledge of gas to lure multiple women in and end their lives. He couldn't perform in the bedroom without violence, resulting in his need to pick up prostitutes to feed his appetite. After bodies were found in his apartment, he didn't deny killing them. He did attempt to make himself the victim for each woman involved. After his confessions, he found the noose. 

Sources:

Rosewood, J. Lo, R. 2016. John Christie. The true story of the Rillington Place strangler

https://artsandculture.google.com/entity/john-christie/m066_tr?hl=en

https://allthatsinteresting.com/john-christie

https://www.theguardian.com/theguardian/2012/jun/26/archive-john-christie-death-sentence

https://trove.nla.gov.au/newspaper/article/62499428

https://londondarktourist.com/john-reginald-christie/