Can someone explaing about knot..

It's the same when a male in real life pregnants a woman

The knot is Cumming inside and then locking the two people together using the alphas dick (there's like an inflatable bump? that locks inside the omega) so the seed takes root in the womb during heat. Dogs use this method irl so you could search that and it might help better than my shit explanation lol

no, its like when they cum the penis grow a plug so they can continuously cum without pulling out. usually abo universe is based on canine cuz wolf lol