What does 背着 mean in the novel 活着 (pp.10-12), e.g., ...让她背着我回家...? I encountered 背着 thrice in quick succession in the novel 活着 (pages 10 through 12):

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。...
... 我就把那个胖大妓女从床上拖起来，让她背着我回家，叫了抬轿子跟在后面，我到了家好让她坐轿子回青楼。 ...
... 那妓女嘟嘟哝哝背着我往城门走，说什么雷公不打睡觉人 ...
... 在两旁人群的哄笑里，妓女呼哧呼哧背着我小跑起来，嘴里骂道： ...

In each case, the 妓女 (sex worker) is doing 背着 to the main character &quot;我&quot; (&quot;me&quot;).
None of the verb definitions of 背 seem to fit these sentences: to be burdened, to carry on one's back, to turn one's back, to hide something from, to learn by heart, to recite from memory.  Perhaps it's grammatically possible she's physically carrying him or her back (?), which seems implausible.
Question: What does 背着 mean above?
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)