This is so weird. And curious. (sorry it's gross)

We have a second story deck. The only access to it is through the room it's off of. (no outside access/stairs)

The storm door is broken and doesn't close all the way. We don't go out there much since I have little guys and keep it locked for now.

Anyway - found mounds of critter droppings on the metal door frame where something had to have backed up and left a deposit there purposefully, and repeatedly. Looked like a cow had been there actually.(or someone who was sick and couldn't wait for the bathroom just opened the door and stuck their butt half-way out! lol Thankfully we have no one here who would do that!) lol Must've been swollen from the rain. (ewww. I know)

Anyway. DH cleaned it all. We sprayed the area down with vinegar and lysol. Closed the door as closely as possible, but there's still about a 8 inch opening or so.

Checked a few days later - it's back. I have no idea what is doing this. It must be climbing the tree right by the deck and using the door frame as facilities.

My question is: How can I stop it from coming back. Even once the door gets fixed.

Also, curious what the heck it could be! lol Maybe a coon or opossum? Are there critters who have 'litter box' habits? Or privacy issues? Why would they come find *that* spot in the first place?