If you want to get as close the stage as possible, you should get Innenraum tickets. And you and your girlfriend both should be members of BSWJBJ fanclub. There are no front row tickets, the only way to get there is to queue the whole day.

American XS was just for presale in November, now you have to buy the tickets from general sale. But I don't think there are Innenraum tickets left (but I'm not sure).

Sorry that I couldn't help you more.

Taija