I'm not even sure I want to explain this one. Let's just say, two teenagers and one infant were involved. And thank God the baby didn't choke to death. I loved nannying the baby, but sometimes I was at a loss when it came to the messes we came across at their house due to the teenagers. This is one that Google only got me part way on.
At first, Google told me to use straight up rubbing alcohol, as to avoid water marks. Brilliant! It dries more quickly than water!
Unfortunately, the sticky dried on mess needed more work to melt off, or something. I was just rubbing it around. So I heated the rubbing alcohol in the microwave. Don't do that. It bubbled instantly and smelled up the kitchen, and I'm sure the fumes shortened my life. And the hot rubbing alcohol didn't work either! It cooled instantly when the air hit it on the couch.
Hot soapy water fixes everything. I mixed two drops of dish washing liquid with 1/2 cup boiling water and 1/2 cup rubbing alcohol. The marshmallow melted slightly, pilled up and wiped cleanly away. And some of the old stains on the couch came up too!
Success! Not perfect, but way better than the comparison to the right. And no more marshmallow. Have you ever had a particularly tricky mess to get up?