Sakura is flat as a board, in chapter 700 she simply used the Tsunade big boobies trick to grow some stuff there to look more feminine because she was always envious of other girls especially Hinata.
manga facts =>
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Karin is simply Sakura 2.0 aka a grown up inner Sakura from part 1, Kishi split the character in 2 parts and by doing this, this character never really left Sasuke's side and had the chance to express its hidden desires toward him and its aggressive personality even more.
Karin's attitude toward Suigetsu mirrored exactly Sakura and Naruto relation ship from part 1 => childish fights, insults all the time, no respect for each other, teasing about Sasuke etc
never wondered why Sasuke's Taka team from part 2 look exactly like team 7 from part 1 meanwhile his previous partners really matured and changed a lot?
this is not a coincidence Sakura saved Karin and Karin sensed Sakura's love for Sasuke, they looked very similar, they acted the same and both shared the same interest for him.