As with anything on the internet, people create their own definition, but the core definition seems to be:
Free Use is a sexual kink or fetish where one partner consents to being available for sex at any time by the other partner without needing to ask for permission each time.
For it to work in reality the couple needs to agree on what is allowed and what isn't, and to set clear boundaries for when things can happen. And of course the person giving free use needs to be able to pause the dynamic whenever they feel that this is needed.
Most of what is on the internet on free use is fantasy, and almost all is a female giving her partner free use of her. But the definition allows a male to give free use. You are probably ahead of me, and thus are not surprised, when I say that Devotional Sex is one way for a man to give free use to his partner and for a woman to have free use of him.
With Devotional Sex he commits to fulfilling all her sensual and sexual wishes for all the time he is her Knight. This might be just for a Season (say for a week or two) or the couple may have agreed to live this way. With Devotional Dating and Devotional Friends he is her Knight whenever they are together.
With Devotional Sex he only has to fulfill her wishes within what he is willing to do at that time, and overall she has to keep him equally happy. But as she is tuned in to how he feels, in practice she only has something happen when she thinks that he will, once he gets over any surprise, bewilling (or keen) for this.
Of course the Princess has free use of him whenever they go to bed or wake up together. But as he is her Knight at all other times, some of the most fun is when she has something happen outside the bedroom.
A common activity is Affirmation as she only needs to say "Reveal" and he will remove all his clothes and stay naked until she ends the Affirmation. She can also say "Display" at any time and he will stand in front of her and gently play with himself to get hard for her viewing pleasure. If he is wearing clothes when she says "Display" he will pull down his trousers and Display to her. During Display she can just watch, or she can arouse him with her hands or mouth. If she ever says "Pleasure" he will go down on her and either kiss her over her clothing or give her oral sex. Of course she can also enjoy other sexual pleasures.
With Devotional Sex this free use isn't just her making things happen but is extra powerful because she will just end activity whenever she wishes.
Free use in porn:
With porn the fantasy is almost always the male viewpoint. So most free use porn is created to push the male fantasy of him being able to have sex with a woman whenever he wishes.
For a man to make this fantasy happen in real-life what he wants is a woman to consent to give him free use.
This is a huge misunderstanding of kink. With pre-internet kink, the key kinky person is the one who wants something done to them. So real-life healthy free use is when the person giving free use not only consents, but it is their kink / fantasy for the other person to have free use of them and for them to often take advantage of this. (It's the same with other kinks such as spanking or bondage. Healthy BDSM is the person being spanked or in bondage wanting this as it is their kink / fantasy.)
With Devotional Sex the Knight has high erotic background energy due to not having ejaculated for many days. So he is always keen for his Princess to start an activity, any activity. If he is taken by surprise he quickly becomes aroused. And though he would like the activity to keep going, even if she soon ends the activity he enjoys her getting him aroused. A Princess using her free use privileges is thus PLEASING her Knight.
Free use as if nothing is happening:
A strange take on free use in most free use porn is that the person who has given free use just lets the other person have their way with them whilst going on with whatever they are doing as if they are not noticing what is happening.
Somehow it is meant to be sexy to have sex with someone who is just ignoring you. For me it is sexy for someone to have the power to initiate activity whenever they wish and for the recipient to quickly get aroused and to enjoy the activity.
With DevS the Knight usually quickly gets aroused when his Princess surprises him with activity. Creating this arousal and his enjoyment from what happens is a big part of what makes the DevS fun for both.
With DevS it is the Princess who can enjoy some activity happening whilst doing something else. For example, if a Devotee couple are sitting on a couch together while watching TV she can have him Affirmed (naked) and she can gently play with him whilst watching. Here it is the Knight who will be paying attention to her hand and his arousal. She enjoys doing this, but can also watch the show.
If she is watching something he has no interest in then she could say "Pleasure" and have him give her a long gentle Pleasure Kiss as she watches. He is immersed in doing this. She is probably now half watching and half enjoying the Pleasure Kiss.
When a Princess has her Knight Affirmed for a whole evening or longer, she is likely to have many times when she forgets that he is naked. But for the Knight as his nudity is sexual, he never fully forgets that he is naked. And he is always looking forward to when she says something, or has something happen, to give him fully aroused again.
Free use in front of others:
Another situation that some porn calls free use is when a man has free use of his partner, and he just starts having sex with her whilst she is talking to one or more other people who are in the same room. Somehow having the other people act as if nothing unusual happening is sexy. (But being porn, sometimes this leads to him having sex with both women.)
With DevS a couple can hold a Devotional Social. This is a social event where everyone in the room has agreed that all DevS activities other than Joy (intercourse) can happen. It's called a Social as the women can all continue chatting as any activities happen. The whole point of this is that it is erotic and that the activities are enjoyed by those doing them and those watching.
Amazingly 41% of couples who live DevS have had the Knight naked and fully aroused in front of others (usually either one women, several women, or a couple). Once the ice is broken this starts to feel like a fun new normal for all, and so most couples will have this happen with the same visitors more than once.
Free Use sexual activity with others:
Another extension of free use is for this the free use to be extended to include other people. So a visitor can be given free use by the primary person with free use.
With DevS the Knight shares with his Princess what he is willing to have happen with him when with others and what she is allowed to do with others. He also shares how he feels about each possibility. It's then up to the Princess if anything ever happens, and if so what, and with whom.
As always he only commits to do what he is willing to do at that time, and his Princess has to keep him equally happy overall.
So a Knight can give his Princess permission to share her control over him with another woman when they are all together. I know that some Devotee couples have done this.
A Knight can also say that his Princess is allowed to lend him to another woman. This means that he is alone with her and he fulfills all her sexual and sensual wishes within what his Princess has allowed to happen. When with others he is not allowed to have Joy (intercourse) nor to ejaculate.
I know of one Princess who had her Knight visit a friend weekly and she has free use of him, who lent him to another Devotee couple so the Princess could enjoy an evening with two Knights, and who would swap him with another Princess so they both enjoyed an evening with a borrowed Knight.
So for the few Devotee couples who want to explore and enjoy this what would to most seem to be a fantasy has become reality.
Conclusion:
Porn tends to take fantasies to a point where it is impossible for most to experience activities in real-life. What is wonderful about DevS is that by keeping the focus on mutual enjoyment and intimacy in real-life, so many adventures can happen in real-life.
As always I welcome any comments or questions.
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