We really get scant detail here except that the observer got seriously close. The creature then screamed and took off, surely as startled as can be. There is enough ambiguity to even make it a giant sloth as well.
However i do think that Sasquatch works here well enough.
Nothing bad happened either.
My Encounter With The 'Mississippi Monkey Man'
Monday, April 17, 2017
“It was a very hot summer night. I was coming back from Virginia Beach, and me and my girlfriend at the time were together and by the time I had got to Mississippi. I had left Virginia early in the morning in the car. By the time I got to Mississippi, Highway 59, it was already close to midnight, or maybe 1 in the morning. Highway 59 in eastern Mississippi is very, very lonely. You just have Highway 59 with the traffic going that way and the traffic coming this way, and you've got tall trees on both sides and nothing else. Maybe you might have a little rest area or a little Mom & Pop gas station every 15 or 20 miles. But in between there is nothing.
As I drove that night, I was tired and I was on the road from the morning, since the state of Virginia. My girlfriend was already asleep and my little boy in the backseat. Because I'm a night person, I didn't have a problem staying awake. As I drove down that highway, on the side, I saw a man...a man walking, walking kinda fast, looking down. Very tall, loping man that I thought was wearing a coat. I thought, what in the hell is he doing here?, first of all, and why in the hell is he wearing a damn coat on this hot Mississippi night? I said, "Honey, I saw a man walking all alone. I need to help him." She said, "Are you crazy?" I said, "No, I'm not going to offer him a ride, I'm going to give him some money so that way as soon as he gets to the next town he can get a room or buy himself a nice hot meal or whatever."
So I put the car in reverse to make sure that I wouldn't get ahead. I was already about 2000 feet ahead of him but I was going in reverse and he was closer to the woods. He was actually on the shoulder of the highway. I stopped the car and he stops. He looks at me and I notice a massive man, and my eyes are trying to adjust to the darkness of the night and I said, "Sir, Sir, I would like to offer you some money, Sir, so that way you could rent a room in the next town." He looks at me, and I realized I was not looking at a man. He made a loud, loud screeching sound that even today my ears hurt and then he ran into the woods. I was so horrified. I got in that car, I said, "Honey..." I didn't say anything else. I put the car in first gear and I drove 85 miles an hour and my girlfriend was like, "What happened? What happened, Honey, what did he do to you?" I said, "Honey, it wasn't a man, it was Sasquatch. I just had an encounter with Bigfoot." Later on I realized that there have been stories dating back to the 1800s and 1700s about the Mississippi Monkey Man. Stories passed on by the slave Indians, people from back then about the Mississippi Monkey Man.”