It's been awhile since KH2 for me, but I feel like the potential for Tifa/Seph is there. They're both out there looking for Cloud, who's looking for Aeris, who is... chilling with Yuffie and Squall.

Tifa and Seph meet up in Radiant Garden, epic four-way fight scene between Sora, Heartless, Seph and Tifa... she impresses him just a little, enough that while Cloud is still his main obsession he can take a little time out to play with her... then, maybe the two of them go off on a whirlwind Cloud-finding adventure...

Eh. Just a thought.