Batgirl and Supergirl have be forced into a maze and must find their out so that they can save Gotham City from an attack.  Unfortunately, both girls have to pee.  (Batgirl has to go, but can still maintain an upright walking pace.  Supergirl, on the other hand, is absolutely bursting, but her bladder is still stronger than your average human's.)  To make matters worse, the Maze is designed with a special material that reduces Supergirl's powers (hence why she doesn't just punch a whole in the wall to escape) and is strong enough to withstand explosive cannon fire and laser blasts (so even Batgirl's best gadgets are of no use).  According to the GPS Batgirl is using, they're less than 1000 meters from the exit.  Can the girls make it out, save the city, and get to a bathroom before it's too late?

PS- I wasn't sure who the villain should be, so I'll leave that up to the author. 

Story:  Haruhi, Mikuru and Kyon are spending the day at an amusement park.  While there Haruhi and Mikuru down several cups of water, juice, and soda and, by the end of the day, both girls need to pee.  When Kyon begins to suggest where to find a bathroom in the park, Haruhi instead decides that the group should head back to Kyon’s house instead of using the park bathrooms by saying it would be more interesting.  (The truth is Haruhi has a fear of public toilets and doesn’t want to use them, but she'll never admit that to Kyon.)  As the train is the quickest way back, the group decides to hitch a ride.  Unfortunately for them the train they get on is forced to stop on the tracks when a train ahead of them has broken down at the next station (which is, ironically, the station they need to get to) forcing the girls to wait longer.  With their desperation increasing every second, and no bathroom on the train, will the girls make it back in time?

 Note: I want Mikuru to not make it off the train, and Haruhi to not make it out of the station.  How you do this is up to you, so long as it's PURELY DESPERATION.