I call bullshit on Littlefinger not having a clue what Ramsey is like. Their sigil that they chose to present to the world is a flayed man. Sure, this is a world where people lob off other people's heads and stick them on spikes, but no one else chose a beheaded man on a pike as a sigil. You have animals, and flowers, and fish, and a flayed man. That stands out. There were flayed people when they arrived at Winterfell on display. Do you really need to know about Ramsey's hunts at this point to know you are dealing with a family of sick fucks? Even if he doesn't know anything about the son, he knows something about the father. It's not like they hire people to flay for them, and then put it on their banners.
"I haven't heard anything about him really, but he removes all the skin off a person while they are still alive? I bet once you get to know him he's very cuddlesome. I'm sure the people he's flayed were very bad people and they deserved. I'm sure he completely regrets having to do it as well."
Please. Anyone who knows what the banner of House Bolton is knows what kind of people they are. Even if you use Ramsey as being recently legitimized as an excuse, this show has gone out of it's way to point out family traits. Flaying is the Bolton thing.