There's really not much of a difference except that the Free contract allows the maid to fuck the customers and earn more. Once the training hits a certain level you have to assign a contract type to your maid. Everything changes when you build the first luxury facility and the credits begin to fill your account. The game is very grindy at first and it will take many days before you actually build anything. With the earned credits you have to build new facilities and assign the required number of maids to work there. You also need to earn credits and club reputation so you need to assign jobs to your maids. Leveling up a sex position may unlock some predispositions and kinks.
Having sex with maids increases their yotogi stats.
The more skills you train the more points you get to spend on sex positions in a single yotogi session. Actual skills like singing and dancing and cooking. You need to train the maids so they develop skills needed for the story to progress. And by serve I mean 'perform yotogi', which is what sex is called in this game. Long story short, you are the male protagonist owning a big ass club house which you inherited from your uncle along with his big ass debt and 3 maids (main characters) that will help you manage the club and serve you and the club customers.
