A Joy Orgy is when a couple can have Joy with their partner at the orgy.
With
a Joy Orgy intercourse is not allowed with anyone other than your
partner, but in the group setting the Joy might be happening while one
or both of the couple are also engaging in some contact with someone
else.
Note that what would work best in a Devotional Sex Orgy is
when the Joy is done in a slower more sensual style (in the Tantric
direction). Hard and fast pumping would change the whole feel of the
activity.
With hard and fast pumping it also becomes difficult to
engage in an activity with someone else at the same time.

A
scene with three people is very common in porn films. And the most
common activity with three people is to have a man having intercourse
with a woman, while she gives oral sex to another man or to another
woman.
As
porn is all about action and activity (and rarely includes any
sensuality), the man having intercourse is always pumping away fairly
actively. This causes the head of the woman he is pumping to move so
much that usually you see that she is unable to give oral sex. And if
she does, it is usually just a quick lick before she moves her head
away.

But
if the intercourse is done in a sensual Tantric manner, where there is
little rapid thrusting, but more a slower and more sensual dance, the
woman's head is not forced back and forth, and she is able to give oral
sex while also enjoying Joy.
Not only is she able to give oral
sex, as her attention is no longer dominated by a man rapidly thrusting
inside her, her attention can move back and forth between enjoying
giving oral sex and enjoying the man's sensual dance inside her. Rather
than looking good and active for the camera, she is now feeling good.
The
slower more sensual activity does not look as exciting, but it is far
more erotic and sensual. And not only does it feel better, but when
things are slowed down it often feels natural to keep doing it for much
longer.
To
maintain the Devotional Sex feel of the orgy I also strongly recommend
that even if Joy happens the Knights are not allowed to ejaculate while
at the orgy.
An Open Joy Orgy
is when Joy is allowed with everyone present (not just your partner).
I
recommend that Devotees do not go this far. But it is useful to have a
name for this option for those who do want to do this.