Is that Rin?

The hair and eyes resemble Rin's within an artist's license to interpret, however nothing else in her character does; I'd say no. She's just a twintails girl.

It's say it's Rin. The ribbon on her hair and her thighhighs are a dead giveaway.

It's definitely Rin

That has got to be Rin. There are too many consistent features for it not to be her.

I realize it might look like it at first glance, but there is no way this can be a pov image. Look at the guy's hand holding her arm - he's clearly sitting behind her.