Anus.

Mur-ac - Soreness, crawling, burning, stinging pain in anus.
Aloe - Loss of control; sense of insecurity even when passing flatus;
must hurry to stool.
Ars - Burning pain in anus.
Cina - Intolerable itching, better from cold water.
Grap - Cracks at the anus.
Ign - Constriction of sphincter ani, worse from sitting down.
Kali-bich -Sensation of plug in anus.
Lach - Constriction at anus; drawing and hammering in anus.
Lyc - Pain and constriction at anus during stool.

Nat-mur - Fissures and constriction at anus.
Phos - Wide open; liquid oozes from anus; loss of control.
Plum - Spasmodic contraction of sphincter ani.
Pod - Prolapsus before, during and after stool.
Sec - Wide open.
Sep - Sense of weight or of a ball in anus, not better from stool.
Sul - Redness and itching of anus; prolapse.