Where's the red light district in Edinburgh then...?
It's all over. Like most cities. Look up if you are ever walking down Lothian Road late one evening.
A colleague's daughter ended up living in a flat above one on Lothian Road, her father was absolutely outraged - but she said it was the safest she'd ever felt living in Edinburgh. The stairs were always freshly painted, they had a cleaner in twice a day to keep things spotless, the main door was never broken and there was a bouncer on shift 24 hours a day who was happy to act as a concierge for other residents.
Oddly enough, after her boyfriend broke the neck of his femur skiing, she ended up hiring one of the gentlemen herself one night for a Ceilidh. 20% "Friends and family" discount + they through in complimentary kilt hire (apparently it's a bit of a fetish for the tourists). Had an amazing night.
If the chap is really stuck, could always download a dating app for a one night stand.