Mr. Yeo, Joon Young wrote about his impressions of JaeJung in JJB book (JJ's Birthday book, given to fans at his birthday party).
Episode 02 - 1.
On one day in December, I met JYJ again at a cafe on the first floor of our company's headquarter.
What I felt after meeting [them] twice is that JaeJung was the type who is curious about his surroundings. That's why I got to talk with him for the first time.
While Junsu and Yuchun was immersed in the movie I played (Love Actually) [for them], JaeJung started talking to me after looking at my audio system saying "wow, what is this, this is awesome (really good)."
So I went next to him and explained about the audio system. Then he started pulling books out of the bookshelf and reading them. When I told him he could take a book(s) if he wanted, he picked Alain de Botton.
Then he jokingly picked a love essay (I guess an essay book about love?) and went "maybe I'll get a girl friend if I read this kind of book".
When he saw a liquor bottle, he'd go "I like this liquor",
When he saw an interesting piece of furniture, he'd go "I'll ask you when [I do] interior design later."
He showed interest in this and that and all around and talked [about them].
It was a very short moment, but while I was talking with him, I forgot the fact that I was talking with the most popular idol in the world because he was so sociable and friendly.
I don't know if it's a proper analysis, but this is what it exactly felt like.
A slim (sophisticated?) career woman who, unexpectedly, enjoys eating at Po Jang Ma Cha (a cheap ourdoor drinking place, you see them in Kr shows).
A tough man who, unexpectedly, enjoys cooking.
A chabol (extremely rich people) CEO who, unexpectedly, empties and scrapes the bottom of the bowl of soup and rice that's 3 dollar.
And even more attractive.