The woman was walking in Elphinstone Road at 10.35pm on Sunday when the incident took place.
The man who touched her was in his early 20s, around 5ft 7ins tall, black and of slim build, with an afro in two styled buns.
He was wearing a long sleeve black puffer jacket and black jogging bottoms.
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Police staff investigator Mark Humble said: ‘I appreciate that this is not the clearest of images, but hope that something about it may help you to recognise the man in the picture.
‘This was an upsetting incident and we are keen to speak with this man.
‘Please, look closely at the photo, if this reminds you of anyone you know, please call us and let us know.’
Anyone with information is asked to call 101, quoting 44200215087.
Alternatively, call Crimestoppers anonymously on 0800 555 111.