What order are couplings like 'CharAxCharB' in?
The first one is the dominant one a.k.a. seme while the second one is the receiver a.k.a. uke. For example in doujinshi Puella Magi Madoka Magica Doujinshi Homura x Madoka (available online in online manga sites), Homura will be the seme, while Madoka is the uke.