Annabels was a real knocking shop, although I never visited it one of my work colleagues knew the owner. Dreams, I had a massage there once, it was a proper massage but after a while the masseuse said to me 'I think you know what sort of establishment this is'.
I am guessing that sexual services are available as the website mentions happy hour is between 11am to 4pm. If it was a respectable establishment there wouldn't be special offers for normal daytime hours. Also, services on offer are almost exclusively massage. A proper male grooming establishment would be offering waxing, manicures and pedicures. Having said that it doesn't say what the opening hours actually are. The longer its open the more likely its a knocking shop. Also, it may just be handjobs and not full sex on offer.