It's so obvious

[Vilvake]

Kakashi's hand is passing to the left of Rin, and it only looks like it's passing through her. He was probably fending off an attacker that managed to get a hit on her. Obito probably saw it at an unfortunate angle, freaked out, and ran off to cry or something.

 

[-Carnage-]

did you not see the arm going through her....troll fail...obviously your an alt that didnt want your real account to get flamed....

 

[-Shiro-]

no in your dreams my freind that hand is in her in the worst possibul way

 

[Yusuke Urameshi]

When Obito saw through Kakashi's eye, it was through Rin's heart, so.... The only thing wrong with that is that it looked like it was in Kakashi's right eye's POV, not his left, but nonetheless.

 

[AP2k]

He looked her in the eyes and cried. Not a lotta situations make a guy do that.

 

[Vilvake]

Huh. Somehow I missed that arm on page 17.