How come when I put my finger in my butt I poop?

When you insert a finger into the rectum, it can stimulate the rectal walls and activate the body's natural reflexes. This stimulation can trigger the defecation reflex, leading to the urge to poop. Additionally, the pressure applied may help move stool closer to the anus, making it easier to evacuate. It's important to practice safe and hygienic methods if exploring this area.