Bradley Onfroy and Josie Hollis are accused of killing Jordan Hill.
Mr Hill died in hospital after being found with injuries at a flat in Southey Avenue, Sheffield, on 23 March.
Mr Onfroy, 31, of Badger Close, Sheffield, and Ms Hollis, 24, of no fixed abode, appeared at Sheffield Crown Court and were remanded in custody to stand trial on 20 October.
They also denied robbery.
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