On the character selection screen in Samurai Warriors 4, some character portraits have a little smiley icon, depending on which character is selected as the primary one. As far as I can tell, this is not mentioned in any of the in-game tutorials.
I could not find a screenshot of the character selection screen, but you can see the icons on four characters at 1:33 in this youtube video. If a different character than Oda was selected first, these icons would appear on different characters, so they seem to signify some sort of relationship between pairs of characters.
These icons appear from the very start of the game (so they are not something you need to unlock).
What exactly is affected by choosing a pair of characters with this icon? Also, is it possible to change these relationships through the course of game?
Best Answer
According to this wiki, it merely indicates which characters have a good relationship, triggering duo-specific lines during battles:
It isn't clear whether it changes anything else, though it may give an initial hint as to which duo is likely to have duo-specific objectives. This hint, though, pales in comparison to simply checking out the objectives list after a single attempt.