Aeris and Tifa appear to form a connection almost immediately, despite uneasiness over their apparent status as 'love rivals' for Cloud's affection. Despite Cloud's protestations, Aeris insists on helping him track down Tifa in Wall Market over concern for her well-being, and they infiltrate the mansion of Don Corneo (a mafioso on Shinra's payroll, living in the slums to collect intelligence about AVALANCHE) together.
Cloud, embarrassed by his appearance — having dressed as a woman to bypass security and the Don's "no men" policy — leaves Aeris to introduce herself to Tifa personally. While things are at first awkward between them, each warning the other not to misconstrue their relationship with Cloud, the humour of the situation prevails: there is something about Aeris's earnestness which charms Tifa, despite her misgivings, and the two find common ground in teasing Cloud for his ideosyncrasies. They form a connection and understanding as women in a group of men, experiencing the same frustrations and concerns, despite being radically different in terms of personality and background.
The extent of Tifa's trust and concern for Aeris is apparent very early in the game: she entrusts Aeris with Marlene's safety, opting to go with Barret and Cloud herself to try to prevent the collapse of the Sector 7 pillar. When the group learns of Aeris's capture by the Turks she insists on rescuing her in the face of Cloud's protestations, and has a visceral reaction to hearing Hojo describe her as an 'animal': "That's terrible! Aeris is a human being."Cloud: No, Aeris! I can't have you get involved.
Aeris: Oh? So it's all right for Tifa to be in danger?
Cloud: No, I don't want Tifa in...
There are tense moments between Tifa and Aeris; because it is important to Aeris that she know and understand Cloud, she has difficulty avoiding treading on Tifa's toes — in general, Aeris has trouble with social boundaries. But there is no resentment on Tifa's part, and Aeris never displays any hint of jealousy over Tifa's relationship with Cloud either.
Tifa more than any character other than Cloud expresses interest in Aeris's history and heritage: she pays attention when Aeris is talking about her background, about what it's like to be a Cetra, to be the last Cetra. Tifa understands loneliness, and realises that Aeris also experiences feelings of isolation; seeing Aeris keep these feelings to herself and take risks with her emotions is part of what inspires Tifa in the second half of the game to be more outspoken about the way she feels and what she feels her role should be.
Tifa too is the one who talks Cloud into following Tifa after Aeris leaves the group, because Tifa as much as anyone else can't bear the thought of losing Aeris and having to face the rest of their journey without her: "What'll we do," she says, "if something happens to Aeris?" And after her death, Tifa is the one who reacts the most visibly: she strokes her hair back out of her face, and is unable to stop herself crying. She is the one who offers the deepest insight about Aeris and her motivations after she is gone; she seems to have dedicated a lot of thought to her.Aeris: All I know is... The Cetra were born from the Planet, speak with the Planet, and unlock the Planet. And... then... the Cetra will return to the Promised Land. A land that promises supreme happiness.
Tifa: ...What does that mean?
Aeris: More than words... I don't know.
Tifa says that she felt Aeris's presence even after her death. Tifa also seems to feel it in Final Fantasy VII: Advent Children, realising that Aeris has been "watching over" Cloud, and thanking her for it.Tifa: I wonder what Aeris felt, when she was on that altar...?
Cloud: I'm sure she wanted to gve her life for the planet...
Tifa: Really? I wonder. I don't think that's it at all. I think she didn't think she would die at all, but that she planned on coming back all along. She always used to talk about the "next time". She talked about the future more than any of us.
