Original:  In several cases, he was unable to explain why he committed the murders: this was the case with Hardy, with whom Benjamin had an intimate relationship, but after doing drugs together, he said he strangled her for no apparent reason.
Revised:  In several cases, he was unable to explain why he committed the murders: this was the case with Hardy, with whom Benjamin had an intimate relationship, but after doing drugs together, he sodomized and strangled her for no apparent reason.
Edit intent: meaning-changed