LOL imaging this crack pairing is hilarious! Naruto would be so intimidated by her! If Karin kept trying to make moves on him the way she does with Sasuke ... well it'd be funny, but she'd drive him away so fast. xD I don't think Naruto's comfortable with girls that straightforward.
It reminds me of that filler girl who was flirting with him, trying to give him the "kiss of death", and while he was running away from her he said he wasn't good with girls like that lol.
NaruKarin is a funny idea for crack, but realistically speaking Naruto showing feelings for anyone other than Sakura would be too out of character to picture. Don't crack ship it, but least you know whatever it is the ship would have comedy.