A variation on the sex position "Acrobat" in which the Receiver is laying on top of the Giver, back to stomach.
A more intimate sex position, this will allow the Giver more access to the upper body of the Receiver.
It does make the penetration angle more difficult, however.
With the Giver (the one doing the penetrating) laying flat on their back, their legs slightly spread apart, and upraised slightly.
The Receiver (the person being penetrated) lays on top, facing in the same direction.
Pulling their own legs upwards, the Receiver is then presenting their rear, for penetration, though the angle is more difficult, for easy penetration.
Usually their arms are outstretched in a 90 degree angle from their body.
In most instances, the Receiver's legs are more tightly together, though spreading them apart, slightly, might allow for easier and more enjoyable penetration.
However, spreading the legs too far, can lead to instability for the Receiver.
The penetration and thrusting generally rests on the Giver, with little assist from the Receiver.
The majority of movement, comes from the Giver.
The legs of the Receiver are usually held upright, not resting on the upraised knees of the Giver.
Positions such as this, known as the 'spoons positions' may be more applicable when one or both partners, have serious back conditions.
Physical limitations can make many of the various sex positions, impractical.
Height, weight, mobility, all help determine the practicality of which sex position is best, for those involved.