You decide that maybe you should help infect the world, it's what infected do anyway, and you have nothing better to do, so why not?
Over the next year you help the the infected infect the rest of the planet, and eventually, you and the others succeed, but after all is said and done and everyone has become sexy inklings and octolings, you begin to feel empty and alone. Despite showing the rest of the world your love and helping the infected out, you never really connected with anyone or thought about what you'd do after the infecting was all said and done, and so, you live out the rest of your time on the planet alone, wondering that maybe, just maybe had you done something differently, things would be better.
BAD END