There is a surprisingly large Asian community in Helsinki. I don’t mean to sound racist but I did not anticipate that in this part of the world. That means there are tons of (Asian) massage parlors, especially around Kallio. The massage part can be a bit hit and miss, but they’re usually up for happy endings. The Thai erotic massage studios in shady malls go as far as full service. A session will cost you about €100 on average.
Thai Massage Helsinki (https://www.magichands.fi/) at Hollantilaisentie 9, The Oriental Thai (http://www.theorientalthai.com/) at Ruoholahdenkatu 16, are safe bets. There are some real gems if you’re looking for something special, like Helsinki Bardot (https://www.helsinkibardot.com/). This independent masseuse in Helsinki might be a bit on the pricey side but I dig her approach to the art of erotic massage.