What does 背着 mean in the novel 活着 (pp.10-12), e.g., ...让她背着我回家...?
我年轻时吃喝嫖赌，什么浪荡的事都干过。我常去的那家妓院是单名，叫青楼。里面有个胖胖的妓女很招我喜爱，她走路时两片大屁股就像挂在楼前的两只灯笼，晃来晃去。她躺到床上一动一动时，压在上面的我就像睡在船上，在河水里摇呀摇呀。我经常让她背着我去逛街，我骑在她身上像是骑在一匹马上。...


The first section of text already makes it clear that 背着 refers to the 妓女 carrying the narrator on her back. (because she was fat enough and the narrator felt like he was riding a horse)