Traditionally, this is a sign ruled by Saturn, and it is clear how detached and unemotional this planet can be.
They aren't aggressive people per se, but they can be a little mischievous in this area.
Aquarius is the sun sign that rules over people born between late January and late February.
Some people are confused and think Aquarius is a water sign, considering the word "aqua" in the name, and considering the symbol for Aquarius is the Water Bearer.
Since he's probably not concerned as to what other people think of him, he often doesn't bother forming opinions about other people's behavior; a 'live and let live' attitude may be evident.
Along these lines he's very unlikely to be into gossip, or to ever be petty.