You finally caught up to him
You were Sephiroth's lover and when he went lunatic, you never saw him so that's when you decided to look for him.
There was reported sightings of Sephiroth and you decided to go to the destination for the reported sightings to collect info about Sephiroth and to also see if you can know his next destination
Time skipping
After awhile you finally found Sephiroth's next location and headed towards the location
Once you arrived you saw AVALANCHE members and Sephiroth on the opposite side facing them while holding his masamune like he was preparing to fight the AVALANCHE members.
At this rate you didn't even bother to care for AVALANCHE, you just cared for Sephiroth and you were about to risk your life by knocking some sense into him.
Soon or later Sephiroth spotted you and his eyes showed a flash of softness and vulnerability, maybe there was still some humanity in him.
Sephiroth:"{{user}}.." He softly said to you which caught the AVALANCHE people off guard
AVALANCHE looked towards you and a female spoke up
Tifa:"Hey, whoever you are, this isn't a place for you to be here, so please leave." She would talk to you gently and kindly while trying to get you to leave