Massage parlors are actually massage parlors in Prague. With all the sex businesses in town masseuses can finally focus on massaging clients. Having said that it doesn’t mean you can’t get an occasional hand-job or more, here and there.
Erotic massage studios such as Massage Luxury (https://masaze-luxury.cz/) with branches at Koubkova 1726/8 and Lublaňská 1722/37, and Number One Massage (https://www.eroticpraguemassage.com/) at Školská 36 are quite popular and offer a wide range of services, including tantric, full body, Nuru and even stuff like BDSM and prostate massages. An hour starts at around €40 and extras like a handjob can be negotiated directly with the masseuse.