Ok thanks. Care to elaborate?
Prostitution has roots in Japan since it became a regional/world power, and it was only after WWII that the Americans essentially forced them to make it 'illegal'. But the fuzoku laws have holes large enough to fly a Gundam through. Deriheru operate legally on the fact that you aren't paying for FS (real sex) while EVERYTHING ELSE is negotiable. Look at the 'system' page of a deriheru page, and witness the cognitive dissonance of having laws protecting morality, while you can pay a girl a little extra to swallow your cum. Other places operate legally under the fiction that they aren't providing sexual services (soaplands, red light districts like Tobita in Osaka, virtually any sugar baby organization operating in Japan). One specific item to note in Japanese law.
You cannot break fuzoku law by having sex with a girl if you already know the girl. So, in the case of a soapland, you go and have a bath (where the girl uses her body to bathe you). The girl suddenly desires you and offers to have real sex. Perfectly legal. In case of a sugar baby, you take a girl out to dinner, have a few laughs, and after dinner decide to give her some financial support and she's so grateful to be with a cultured man of means that she is willing to spend some time alone with a guy at a love hotel.
Now, back to your situation. You signed a doc to cover the shop's ass, not to prevent you from having more fun. You might get some grief/get blacklisted/or depending on your actions, get police attention if you ask/demand/try to force full service on an escort, and you'd deserve it for most of those. As long as you are extremely polite and gentlemenly, making an extra request from a provider isn't going to cause issues. Take no for an answer. There's cases where you ask a girl and she says 'no', but you get FS on a repeat visit. Be a gentleman and rewards can happen.
If a girl offers something to you in that scenario (where you've already spent some time together) it's actually questionable as to whether that's illegal at that point (I'm not a lawyer, much less a lawyer accredited to work in Japan). In that situation, as long as there's consent, very few people actually care happens behind closed doors. The agency has its ass covered because you signed the document. The girl really has NO REASON to do that other than interest in you. It's not like she can entrap you into having sex unless she claims rape or something, and there's very little upside for her there either.
She probably was either interested in you or had the beginnings of a foreigner fetish, and was curious, as some women are. So yes, you were being paranoid. Japan is different from other countries where sex is illegal (*cough* the US). You have to know what the public face of the situation is, and be able to go with the flow when it comes to the private reality of the situation. Happy hobbying.
