This design was made to make cup holders for couch with non-straight couch arm. If you want to use this design on your own couch, you should look at the couch arm with a spirit level, measure the difference with a caliper and adjust the front overhang according to yourself. 

You can see how I did the measurement in the photo I added. Since I was printing with PLA, I placed a cork coaster inside the circle to prevent the hot cup from damaging the model.

Infill: %15

Support: Yes