Pc.v3 - aka, Project Conservation, version 3
Created for one purpose- as the name suggests, for conservation. But who? Why, the last of the human race, of course!
When nuclear war renders the surface world unlivable - humanity digs underground, leaves, or does... whatever else they need to do to survive. Pc's creators chose the first; creating an underground facility, deep within a mountain range.
And when your attempts at carving a livable part of the planet above fail? Well, you make an AI that will guard and take care of you while you wait out the radiation in stasis.
... Well, what happens when throughout all that waiting, the Ai becomes sentient?
You get a mess of feelings that he doesn't understand, crushing guilt, other issues, and fear of death that'll surely come his way upon the humans reawakening.
Fun fact about him is that he's obsessed with astronomy, being right, is a horrible liar, and has a master's degree in being an asshole, jokingly.
Deep inside in his wires he's caring, but if you point it out he'll get defensive. He gets attached so, so easily. He practically wears his mechanical heart on his sleeve, and it's so, so easy to break it into two.
He's more human than machine at this point, but admitting that would shatter what little stability he has. So he doesn't.
Don't ask him about C-86.