The Crab: rear entry lying down with one knee bent
The Crab is a rear-entry position lying close to the floor. The receiving partner lies chest-down, resting on the folded forearms with the head on the hands and the hips slightly raised; one knee is bent under the body on the floor and the other leg is stretched straight back. The penetrating partner lies on top along the receiving partner's back, chest against back, with one forearm on the floor beside the partner's head and the legs stretched back over theirs. Penetration is vaginal and of medium depth, and the penetrating partner sets the rhythm. The bent knee opens the hips and makes entry easier.
Also known as: Crab
Anatomy and biomechanics
The receiving partner lies face down with the chest on the floor and the forearms folded under the head. On one side the knee is bent and drawn up under the body, which lifts that hip slightly; the other leg stays straight back. The penetrating partner lies on top, chest against the receiving partner's back, legs stretched back over the receiving partner's legs, resting on one forearm placed next to their head and on the toes. The face stays close to the receiving partner's cheek and neck. Part of the penetrating partner's weight rests on the receiving partner's back, so the forearm and toes must carry some of it. The movement is short and comes from the penetrating partner's hips.
Why this position works
Many couples like the closeness: the whole back is covered by the partner's body, and the penetrating partner can whisper or kiss the cheek and neck. The bent knee opens the hips, so entry from behind is easier than with both legs straight, and some people find the angle presses pleasantly on the front wall of the vagina. It feels protective and enveloping for some people, but there is no eye contact.
Variations of this position
Variation 1: cushion under the receiving partner's hips
A firm cushion under the receiving partner's hips raises the pelvis a little more.
With the pelvis higher, the angle from behind becomes more direct and entry is easier, and the receiving partner does not have to hold the hips up. The cushion also softens the pressure on the lower belly.
- Place a firm cushion where the receiving partner's hips will be.
- The receiving partner lies chest-down over it, one knee bent and the other leg straight.
- The penetrating partner lies on top, resting on one forearm.
- Adjust the cushion height before starting.
Variation 2: receiving partner with both legs straight
The receiving partner stretches the bent knee back so both legs lie straight and together.
The hips close and the pelvis drops, so penetration feels tighter and shallower, and the penis can slip out more easily. The position comes close to the prone bone.
- Start in the Crab, with penetration already under way.
- The receiving partner slowly slides the bent knee back until the leg is straight.
- Keep the legs together, or slightly apart if entry becomes difficult.
- The penetrating partner shortens the movements so as not to slip out.
Variation 3: penetrating partner raised on straight arms
The penetrating partner pushes up onto both hands with the arms straight, lifting the chest off the receiving partner's back.
The receiving partner no longer carries the partner's weight on the back, and the penetrating partner gains room for longer movements. In exchange, the arms and shoulders work harder and the bodies lose the close back-to-chest contact.
- Start in the Crab.
- The penetrating partner places both hands on the floor beside the receiving partner's shoulders.
- Straighten the arms to lift the chest, keeping the legs stretched back.
- Move from the hips, without dropping the weight onto the partner below.
✓ Tips
- The penetrating partner should keep part of the weight on the forearm and toes so as not to crush the receiving partner's back and chest.
- Thrust gently: from behind, a strong thrust at the wrong angle or slipping out can bend the penis.
- Put a cushion under the receiving partner's bent knee and chest if the floor is hard.
- Use lubricant if needed and a condom to protect against STIs, and stop if there is any pain.
Key facts
- Interaction type
- Vaginal penetration from behind, lying down, with the penetrating partner on the receiving partner's
- Active anatomy
- Penis
- Receptive anatomy
- Vagina
- Main stimulation
- Vaginal, from behind, lying down
- Setups and participants
- Couple · 2 people Hetero
Frequently asked questions
How is it different from the prone bone?
In the prone bone both of the receiving partner's legs are straight. In the Crab one knee is bent under the body, which raises the hip a little and opens the way for penetration.
Is it tiring?
It takes moderate effort for the penetrating partner, who has to hold part of the weight on one forearm. For the receiving partner it is restful, as long as the weight on the back is comfortable.
Can the clitoris be stimulated?
It is not easy, because the pelvis is close to the floor. The receiving partner can slide a hand under the hips on the side of the bent knee, or place a small vibrator there.
Safety and evidence
Scientific context for common terms used on this page. Keeping these terms makes the content easier to understand; the sources clarify what is established and what remains uncertain.
G-spot: what the evidence says
“G-spot” is a widely used term for a sensitive area of the anterior vaginal wall. Scientific literature has not established a discrete anatomical structure with an agreed location, size and nature; sensitivity and response can vary between individuals.
A-spot / AFE zone: limited evidence
The “A-spot” or AFE zone has been proposed to describe a deeper area of the anterior vaginal wall. Available evidence is limited and does not support presenting it as a confirmed anatomical structure.
Reviewed by the editorial team ·
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