[[WMG:Katia's lowest point is still ahead of her.]]
… and when it arrives, it will make [[spoiler:getting robbed by Sigrid]] look like nothing. Following her latest setback, Katia will get back on her feet, and there will be an even longer period of things looking up. Katia will become involved in (a) quest(s) more important than delivering letters. Then something bad will happen. Disaster will strike. Everything our hero achieves will be undone. Overcoming this will be the zenith of Katia's character development. HolyShitQuotient will be high. Mark my words.
[[WMG:Katia is the Champion of Cyrodiil.]]
She's got quite a ways before she's going to be closing shut any jaws.
[[WMG:Gharug gro-Upp's luck will run out, resulting in his death]]
His death may be at Katia's hand, possible due to his sole piece of bad luck up until this point rendering him unable to wear a ring of fire resistance. Either that or Asotil will find him.
* Seeing as how he's a Highway you kill in Oblivion, we already know how he dies, and assuming Katia is the prisoner, it will be by Katia's hand.
[[WMG:Prequel is a tragedy, and things will not end well for Katia.]]
It's well and good to say she must be the hero and that, but, well, the hero in Oblivion has a really boring story. Kazerad has done an exceptional job in showing us how [=NPC=]s and such can be extremely interesting characters in their own right. It would follow that Katia could be herself a very minor character. She may very well have a significant effect on events that would follow, but there's a lot more roles in a story other than The Hero.