Spoiler (click to show/hide):
As I recall you specifically recalled this one to be more you fathering children then the other way around... and I do generally view getting a breeding pet as something you have to work for... and relatedly you will eventually knock the smug shortstack up(and her whole team,) and probably as one of the first, but remember... you have just acquired super-powers, and you're facing someone who has super-powers, and while yes they are weaker, she knows how to use them. You're not going to just curbstomp her. It won't be likely but you could win here... the point is more to show the character does have plenty of room to grow. If that can be accomplish with you managing to pull out a win since yes, you are being underestimated, I don't mind a win... though probably not the best to immediately fuck her on the spot since this isn't an empty building.
The portal is strange... it doesn't seem like it's coming from the shortstack... or even the device, but more like it was cast remotely. Stepping through you find yourself in a mass gymnasium, big enough to fit a football field into... actually that might have been what it was at one point, but now the walls are padded, the ground is soft, and any seating is behind one way-reinforced glass. As you marvel, the smug girl enters behind you, dismissing the couple of people in the room, before stepping some distance away, "So this is the pride and join of the magic engineers. Short of throwing city block busting magic, this can contain any magic we throw around, and even make sure we don't accidentally kill each other. Though we don't have to take it that far. I'll even let you set the rules."
Random person in the comments section of a random hentai manga- "Now I am ashamed of myself."
Me- "Posh, shame is for fools and people with friends... we need no such things, we have the internet."