I walked in the exam room and to my surprise I see Ashton waiting for me once again. I couldn't believe my eyes when I saw him, I thought we've seen the last of him after what Dr. Topinbotom has done with him but I guess I was wrong. Of course Ashton was asking for his refill for his medication so Doctor PhingerPhuk told him he's going to have to work for his prescription. Dr.PhingerPhuk has Ashton remove his shirt and listen to his heart and then weighed him and then felt around his lower abdomen. He then had Ashton remove his pants and was wearing a black jockstrap. Since this was Ashton's 4th visit he knew how to work the doctor's over and get on there good side so Ashton teased the Doc with his new jockstrap. The doctor then administered a new vapor which made Ashton a big dizzy and sleepy. That allowed Dr.PhingerPhuk to place Ashton's legs onto the stirrups and open up his ass and start placing in the new experimental toy called the Assinator. Ashton come back to reality as the Doctor was inserting the large Assinator into his tight rectum. The doctor gave Ashton more vapors and he became dizzy and sleepy once again as the doctor inserted the Assinator deeper into Ashton's tight hole and was pumping him with the electronic dildo. I increased the power to the Assinator, as Ashton was taking the toy deeper into his ass, as for all the patients, Ashton was the first to take the whole Assinator into his rectum. The doctor pump the toy in and out of his ass, while playing with his dick. Ashton didn't get that hard but he was enjoying the torment that the doc was doing to his ass, going deeper and the buzzing of the toy increased making Ashton feel hornier and hornier. Then the doc removed the Assinator and then thoroughly examined Ashton's cock and was stroking it up and down. It took him a few moments to get hard as the doctor kept on stroking. He then administered the Assinator once again but kept it near the opening of his anus while stroking his cock. Ashton took over and stroked his cock and this allowed me to continue working with the Assinator. The more Ashton stroked, the harder his dick got and it allowed me to once again push his limits to it fullest by inserting and shoving the Assinator in & out of Ashton now loosen rectum. Ashton then bucked his hips and started cumming, this was the most cum I've seen Ashton produce squirting much of his cum onto his jock as I continued to tease his cock and balls and rectum with the vibrating Assinator. I told Ashton I was not finished and I asked him to go to the college gym and get cleaned up and return back within an hour. I had more patients to see but my experiment with Ashton was not complete, I had other kinks in store for him that he's unaware of when I see him back in hour.