While modelling a character, I modelled the legs separates but now I want to merge both objects at the crotch area, but whenever I press "M" to merge the vertices at the crotch area I get a totally different result. It doesn't matter if I select "At Center" or "At Cursor" or anything, I still get this same result.
So here's what it looks like before pressing "M" (with the faces I want to merge being selected)