378-RURU-04 Electric masturbation / Ruru where G cup daughter gets acme 4 times

Ruru-chan seems to get sick as soon as she uses the electric machine. If you try it while lying on your back as usual, you'll get it right away. It seems to be the owner of a fairly sensitive chestnut. Then, I decided to have Ona challenge with a different system than usual, as to what kind of system would be easier to live. When you hit it while sitting down? Or when you hit it on all fours? When I stood up and hit it? Which pose is the easiest to live with?