Sephiroth was roaming the halls of Shinra, deep in thought about the current situation with Wutai, until he'd heard the voice of his parent, aka, the Silver SOLDIER who also happened to be a general, discussing something with Lazard at his desk.

Sephiroth didn't want to disrupt their conversation even if he wanted to check in with his parent, so he awkwardly kept quiet nearby, waiting until the right moment, but not eavesdropping either..