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yaaaaaaaaaaaaaaaaaaay we can stiil voice out meaningless opinions

its turning in to what it used to be guys. Stop.
Anyways Seph is totally awsome and y does he think jenova is his mother?

Sephiroth
"It's your first time back to your hometown in a long time,
right?"
"So how does it feel?"
"I wouldn't know because I don't have a hometown..."

Cloud (offscreen)
"Umm.... how 'bout your parents?"

Sephiroth
"My mother is Jenova. She died right after she gave birth to me.
My father..."

(He laughs.)

Sephiroth
"What does it matter...?"
"All right, let's go."

Cloud enters the bedroom. He passes through a secret door in the
fireplace, down a long spiral staircase, and through a dark cave. He
reaches a secret library, where Sephiroth paces back and forth, absorbed
in a book.)

Sephiroth
"....an organism that was apparently dead, was found in a 2000
year old geological stratum."
"Professor Gast named that organism, Jenova..."

(The camera pans up.)

Sephiroth
"X Year, X Month, X Day. Jenova confirmed to be an Ancient..."
"X Year, X Month, X Day. Jenova Project approved. The use of Mako
Reactor 1 approved for use..."

(Sephiroth walks down a narrow hallway lined with books. He stops and
looks upwards.)

Sephiroth
"My mother's name is Jenova... Jenova Project... Is this just a
coincedence?"

(He looks downward.)

Sephiroth
"Professor Gast... Why didn't you tell me anything? ...Why did
you die?"

Vincent is Sephs father

We know, of course, that Vincent was in love with Lucrecia, however, it is not suggested that those feelings were reciprocated, or that there was even a sexual relationship between them at all. From what we are shown in Vincent's flashback, that Lucrecia loved Hojo is clear -- such as when she rejects Vincent's declaration of love and is seen kissing Hojo a moment later -- and Vincent resigns himself to that fact, saying "If she is happy then... I don't mind," but we're never given any indication either by Lucrecia's actions then or her words in the present that she loved Vincent. In fact, when seeing her in the present, she makes no indication that she feels any such affection toward Vincent, her concern being solely for Sephiroth.

It should also be noted that this flashback first becomes available on Disc 2, after gaining control of the Shin-Ra Submarine. In effect, Hojo's revelation that he is Sephiroth's Father at the end of Disc 2 qualifies as what is considered in story-telling to be a "last minute revelation." It's the last and most definitivie bit of evidence regarding the Male paternity of Sephiroth. Another aspect of story-telling is that the only possibility that has any evidence to suggest toward it is the one that is fact, especially when there is nothing to contest it within the story itself.

That being the case, with there being the evidence of Lucrecia rejecting Vincent for Hojo, showing no affection toward Vincent when seeing him again in the present after 30 years, and with Hojo's last minute declaration -- which is further made "last minute" by the fact that journeying into the Northern Crater for the final showdown with JENOVA/Sephiroth is made available immediately after the showdown with Shin-Ra, the last battle of which takes place against Hojo -- Hojo has to be accepted as Sephiroth's Father until more evidence from the source material (the game FFVII, the film FFVII: Advent Children, the prequel FFVII: Before Crisis, Vincent's game Dirge of Cerberus, or the PSP game Crisis Core) can be brought forth to suggest otherwise, because at this time, there is no actual evidence in support of Vincent being the Father of Sephiroth, and only unsupported assumption can draw conclusions in that regard.