So, if you stab her hair, she will become agressive ? O_O

It's a bit of an exaggeration (though not by much). In one episode, when Pinky thought no one wanted to be her friend any more, she became severely depressed, represented by her hair going flat and straight. (It was like that when she was a child, too, but she wasn't depressed then; it was just a dull childhood.) As her depression deepened, she started losing touch with reality (which is saying something for Pinky) and having dissociative episodes, such as hearing inanimate objects talking to her.

As with many character aspects, portions of fandom have blown this out of proportion for various reasons.

The artist animated Suika pumping air.

http://www.pixiv.net/member_illust.php?mode=medium&illust_id=47220999

jongyon7192p said:

The artist animated Suika pumping air.

http://www.pixiv.net/member_illust.php?mode=medium&illust_id=47220999

See post #1853154

I thought there were no good 4koma. Ill-tempered Pinkie Pie is so very attractive. Behind every successful man stands a woman who won't suffer fools.

sealplayerz said:

See post #1853154

Oh there it is.

Flopsy said:

I thought there were no good 4koma. Ill-tempered Pinkie Pie is so very attractive. Behind every successful man stands a woman who won't suffer fools.

I think you may also have a coincidental fetish for straight hair.

RIP Bart.