Sherri was there at breakfast with Kathlyn. Kathlyn told David that she would be out of town all day and that he was to report to Sherri. Also she told him informed him that his entrance exams would begin next Wednesday and run through Saturday. One test each day. Each test would be scored on a 0 to 250 scale. Each point he missed would count one punishment point. Kathlyn left at 10:00 and Sherri ordered David to strip immediately. She spoke to him.

"Come with me to the library, we are going to start by shocking your balls. Also I want your prick nice and hard for me so start beating it now." Sherri got him to the library and strapped him down face up on the desk. Then she also stripped, taking time to attach a set of metal cuffs to David's balls. Sherri then produced a heavy black box with some buttons, two dials and three wires. One of the wires ended in a standard plug that Sherri connected to the wall. The other two ends ended in clips, one of the clips was black the other red. She attached the black clip to the metal collar she had earlier strapped around his scrotum. The second red clip she attached to his testicles.

She turned the first dial to 10, and the second dial to 15. She spoke to David, "This is 10 volts for 15 seconds." Then she pressed a red button. Mmmmmmmmmmm! The shock was rather mild and lasted only for 15 seconds not too bad actually. More of a tingle than actual shock. She showed him the dials. The first went from 10 up to 2400 and read volts, the second went from 1 to 120 and read seconds. "That was a warm up. If you displease me today, we are going to set this to the maximum of both settings, if you please me we may not use it at all. Still I must demonstrate it's uses. I will give you more three samples. These samples will count for 30 points, total. Here is your first sample." She turned the voltage to 120 and the timer to 120 as well. Then she pushed the button. The electricity raced through his nuts, in a definitely unpleasant manner. Mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm!

"There we go, now we increase the voltage to 600, and reduce the time to 30 seconds. Sherri grabbed onto his cock and sqeezed tightly as she pressed the button with her other hand " Zzzzzzzzzzzzzzzzzzzzzzzzzt! This was extremely painful. David involuntarily arched his body. His cock jerked violently and the electrons coursed through his balls.

"Good boy! Now we increase the voltage right up to 2400 and drop the time to a mere 10 seconds." Again she grabbed his cock, but this time she stroked it a couple minutes prior to pressing the button ZZZZZZZZZT! David arched his body again as painful electrical bursts shot through his gonadal area. His balls jerked up and down for a good minute after the jolt rocked his testes.

Sherri made a couple of calls while David was still strapped to the desk. She crawled up on top of him and ordered. "Okay, now I am going to ride you until I have an orgasm, if you cum I am going to shock you, however, if I get off nice and good, we reduce your punishment by 10 down to 160. Got it sugar? Good!" She adjusted his cock and began working the massive head of his prick into her slit. It felt so good and thick, though a tad painful on entry. David's cock was soon wedged into her tight little pussy, good and tight. Sherri forced her body lower and lower onto his prick, moaning and crying. Her pussy was so juicy, tight and hot David was having a hard time holding back his orgasm. Finally his cock hit rock bottom, though he still had another two inches to go. Sherri was rocking back and forth trying to force in the last little bit of prick. Suddenly her body started vibrating and shaking. Her face screwed into a painful wrenching expression as waves of orgasms crashed into her.

After a few minutes she regained some composure and started unstrapping David from the desk. But she wasn't done with him yet. Oh no. Not yet. She removed the clips from his balls but left the metal collar in place.

Sherri told him to take a shower and to get dressed. He would be responsible for making lunch as well. Then after lunch she had some friends coming over, he would provide entertainment for them. David quickly took a shower and organized his room. After dressing he hurried downstairs to make lunch. He made soup and sandwiches.

Sherri appeared, though she still had the black box with her. She was dressed in white pants and a short rainbow tube top. She seemed to enjoy lunch soon the doorbell rang and Sherri went to get the door. She told him to take the black box and go wait in the living room.

When Sherri came in to the living room she had five girls with her. They seemed to range in age from 16 to 20 but David couldn't be sure. They piled into the chairs and sofas in the living room and then giggling turned to look at him expeetantly.

Sherri assured him that everyone was legal. Then she gave him an order, "I want you to dance for us. Do it now!" David didn't know what to do, so he started dancing, he felt very, very clumsy. Some of the girls laughed and he was embarrassed horribly. They put on some music and soon he was doing much better. Sherri told him to take his shirt off and "Show the girls what you got!" David didn't mind taking his shirt off, though he was somewhat clumsy, it took his mind off the dancing.

All the girls were getting into it now. "Take you pants off too!" One of the girls yelled. Suddenly it was a chant, "Lose the pants! Lose the pants!" Sherri told him to take them off, and so, embarrased, David complied. It wasn't but minutes later that one of the girls grabbed his boxers an yanked them to his knees. His prick sprang out and there was a sudden silence. One of the girls blurted out, "Damn, that is just not normal!" David tried to pull his boxers up but Sherri ordered him to shed them too. His cock was merely semi-erect, in the thick and meaty stage.

Sherri made all of the girls line up, then she paraded David in front of them. David got a chance to examine each of them too. The first had straight black hair and very dark eyes named Nicki. The second was a thin black girl named Tina. The third was an indian girl named Lakshmi. The fourth a red headed teenager with freckles named Candy. The fifth and last was blond with very short hair and she looked about 16 if not 15, named Deedee.

Sherri made him dance and stroke his cock for a while. Sherri warned him not to cum. After the girls got warmed up Sherri let each of them fondle him for one minute each. Then she announced a contest. She said that Kathlyn had offered $1000 to anyone who could make David cum. Each girl was to be allowed 5 minutes, but no penetration was allowed. If the girl succeeded she would get a thousand bucks. If David didn't cum his punishment would be reduced 20, if he did it would be increased 100.

Nikki went first, she ginderly stroked his cock for 5 minutes before giving up. 140 points. Tina was more enthusiastic, jerking his prick pretty actively but still failingm 120 points. Lakshmi wasted no time in getting David's prick into her mouth. By fondling his balls and sucking the head of his prick she had soon earned a thousand dollars. But she didn't stop there she continued to bring him back to performance level before her time expired, 220. Candy was unable to bring him off as well, 200 points. Deedee, had significantly better luck, she stroked him calmly and surely to a screaming orgasm, 300 points. Sherri informed him that he would only be punished for the 160 he still owed her, 140 would be added to his total with Kathlyn. Great now he owed Kathlyn 1765.

Sherri sent David to the shower and told him to meet her in the library at 8:00 oclock. When David got to the library Sherri immediately hooked him up the the black box. She cranked the dial up to 400 volts and set the dial for 40 seconds. Unceremoniously she flipped the switch. Zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzt! "150 points." she turned the dials to 500 volts and 50 seconds Zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz! "140 points! Good boy, I told you not to cum though and you did." then she turned the dials to 600 volts and 60 seconds. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZTT! "Now sperm boy we are warmed up. Let's max this puppy out." ZZZZZZZXXXZZZZZZZZZZZZZZZXXXZZXXZXZXZXXZXZ!"

"Now you are down to 130, you will now fuck me for at least 30 minutes, then if I am satisfied we will shock you one more time then say good night." David achingly waited while Sherri stripped, he spread her legs and slowly entered her juicy slit. He began reaming her pussy. Deeper and deeper he probed until she was completely fucked out. And still he kept loading her cunt up with rigid raging prick. Finally she lay exhausted and sweaty, 40 minutes had passed.

"Well David, I'll let you off for that last ten if you will just get me some water." David got her the water but his balls ached still.