Harper – fighting at Dearne Valley Leisure Centre, just yards from her home in Denaby Main – won every round against the Bulgarian, despite giving up plenty of experience and a considerable amount of weight.
The victory moved the 21-year-old to 2-0 in her promising pro career.
Sheffield fighter Christian Kinsiona earned the first stoppage of his young career against Richard Harrison.
Kinsiona was overwhelming Harrison with shots late in the third round when referee John Latham stepped in.
Doncaster’s Lewis Booth remains unbeaten in six fights after a comfortable points win over Kristian Laight, who is closing in on his 300th professional bout.
And Barnsley’s Ross Blackwell won each of his four rounds against Naheem Chaudhry.