LOL.

At any rate, its pretty much established that Rinoa and Seifer dated the previous year. On the first disc at Galbadia Garden, she says as much:

Rinoa
"I...really liked him. He was always full of confidence, smart...Just by talking to him, I felt like I could take on the world."

Selphie
"Your boyfriend?"

Rinoa
"I...I think I was in love."

Selphie
"Do you still like him?"

Rinoa
"If I didn't, I wouldn't be talking about it. It was last summer... I was 16. Lots of fond memories..."

And of course, on disc two, Seifer basically confirms this with his:

"You gonna fight me too? Rmember last summer when we. . ."

Its also generally assumed that her relationship with Seifer was how Rinoa gained enterence to the SeeD ball, and how she was able to get Cid to help out the Forrest Owls.