I honestly really like how the author just give Peter that tiny end scene. Yes he is only minor typical douchebag that only appear once, but at least he got some peaceful ending.
She was supposed to, given her character when they did the boot camp..
but her negative emotion sucked by the Guide along with the Big peter, so they’re like normal people.
Like others mentioned, the Guide drained her of all negative emotions to power himself back again.
But it's not like that girl has any other choice either, as even her house is basically dead. If she break the engagement with that guy, she would probably not get to marry anyone else.