Now, for some background, read this article on Deadspin about the couple in the bleachers getting it on during an Oakland A's game in 1997.
OK, so you're all up-to-date on where this might be leading? Good.
Because I think I found our mystery reverse-cowgirler, and you can thank my encyclopedic knowledge of mid-90s baseball cards. Say hello to former Phillies prospect...

The backstory DOES check out. He was a first-round pick of the Phillies in '92 and was one of the club's top prospects in the mid-90s. He played with Scott Rolen on the 1995 and '96 Reading Phillies, so it stands to reason that they might have been roommates. And by the time this video was taken, McConnell was already out of baseball due to injuries; so he probably had some free time on his hands.
But come on, the eyebrows and sideburns are a dead giveaway.