Tifa and Cloud
Many people like these two as a couple. I, for one, am not an avid fan of these two together. I have my reasons, of course. But let's start at the beginning, shall we? Cloud had a childhood crush on Tifa, the popular, pretty girl that lived next door to him. Cloud was shy and never caught Tifa's attention much. But once Tifa heard that Cloud wanted to become part of ShinRa's elite military force, Soldier, suddenly her crush on Cloud Strife began. Years later, Tifa finds Cloud once again, only this time Strife appears to be somewhat "whatever" about the whole situation. Actually, Cloud seems to be "whatever" about a lot of his relationships (but his cool exterior in the beginning of the game could easily be explained off by his assuming of Zack's personality). Then Cloud meets Aeris. Aeris, less shy than Tifa, seems to have no problems showing that she likes Cloud. Because of this, Tifa takes the back-seat and never admits her feelings for Cloud. Once Aeris is killed, Cloud becomes even more avid about getting Sephiroth and pays even less attention to Tifa. Then the whole Mako incident takes place, in which Tifa finally admits her feelings for Cloud and helps him to find himself. In Advent Children, two years after the end of the game, it seems that Cloud has secluded himself from everyone else and still keeps his relationship with Tifa as strictly friends.
I think Tifa's love for Cloud is a mixture of friendship loyalty and that little girl crush she had for him when she realized he wanted to become a Soldier. I personally feel that Cloud loved Tifa more as a friend. During the game he never once admitted feelings for Tifa that surpassed anything but friendship. Yes, he had a crush on her as a child. Do I believe it's love? No. Cloud seemed more interested in Aeris, but once she died, Tifa seemed to be a good substitute; even then, he admits no love feeling towards her. Now, I know that other people don't share this opinion of mine, but to me, Tifa could do a lot better (both Aeris and Tifa could do a lot better, as a matter of fact). As Barret pointed out, Tifa wasn't her usual strong self around Cloud. She became weaker and more dependent with him. Not a good thing. More information on the two.
Tifa and Barret
Eh? Lovers, you say? I must admit, that makes for one hell of an interesting piece of fanfiction. These two have a deep friendship, Barret being the first person Tifa probably met in Midgar, and Tifa being like a daughter/sister to him. They certainly love each other, but as family only. Could a love relationship develop? I'll leave that up to the Barret/Tifa fanfiction writers. ;]
Tifa and Aeris
They were friends, but lovers? I don't think so. Tifa and Aeris were attracted to Cloud, not to each other.
Tifa and Vincent
This could work, I suppose. Vincent would understand Tifa's pain, and Tifa would definitely understand his. Plus, Tifa's cheery and kind personality would be good for Vincent. She could certainly break him out of his shell. More information on the two.
Tifa and Rude
Reno asks Rude who he has a crush on, and after much pushing from the red-haired Turk, Rude reveals that he likes Tifa. And that's the last you hear about this. Rude and Tifa never have any dialogue with each other and Tifa never seems to acknowledge his existence, other than "Turks=bad".
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