So I just got to the point where Cloud rescues Aeris from the Shinra building. In that scene, Hojo was trying to have Red XIII mate with Aeris to produce a Cetra with the lifespan of Red's species (Hojo mentioned that the experiments to find the Promised Land would take about 120 years). However, Cloud arrived in just the nick of time to stop the nefarious deed.
But what if he hadn't? Red mentioned he was only acting like he was gonna "get" Aeris so that he could throw Hojo off, and that in reality he had no intention of "getting" her (he doesn't like two-legged things). But for how long could he have acted before Hojo caught on? And what would Hojo have done after catching on?