I have taken ritalin for years, starting in college and it has always made me unbelievably horny. I take it daily to function regularly as specially when I have a lot to do, but I love to set aside a good 12 hours or entire day to take my Ritalin, watch porn, and jack off usually edging for hours on end uninterrupted. In college I would fucks my girlfriend 3 or 4 times a day and she loved it because she had a super high sex drive. A few years after that I started seeing a guy that had never taken Ritalin before and tried it. It made him super horny as well. At first we would just jack off together, but after a couple of mutual masturbation sessions things progressed into blow jobs and then hard core fucking. He would get so unbelievably horny he couldn't control his urges to be fucked hard and long. There were no limits to what he would do. He wanted to please me in any way possible and liked being used and treated like a cum dumpster. It was almost like a Dr. Jekyll and Mr. Hyde type of change in him. When he took ritalin he wanted to suck my cock dry, be pounded for hours in every position imaginable, and have his ass filled with load after load of my cum. We both lived with our parents at the time so we didn't have many opportunities with enough privacy or time to have marathon fucking sessions, so we had to get creative or quick and quiet. We would quickly go down to his basement, he unzipped my pants, pulled them around my ankles, drop his shorts, and would bend over the washing machine and say "Stick your cock in me and pound me hard until you cum. But we have to be quiet and fast because someone can walk down at any moment. So I'd be fucking him and see stream after stream of semen shooting all over the floor and his butthole spasming and contracting around my cock. That almost always sent me over the edge into my orgasm. Then an hour later he'd say "Let's go swimming at my subdivision pool." So we'd grab our bathing suits and towels go into the locker room to change and shower and he'd pull me in the private family shower room, (the only room with a locking door and huge shower with a big bench). We got naked then he told me to sit on the bench. He took out a bottle of silicone lube from his back pack, slathered it on my cock, jumped on the bench standing over me, and impaled his ass on my cock squatting over my lap on his feet. He'd ride me nice and slow, going all the way up and all the way down until he exploded cum all over. Sometimes especially when I'm on ritalin it can take me a very long time to have an orgasm so I really had to do my best to cum as quickly as possible, which would be at least a good 30 minutes to an hour, so after he had climaxed he would ride me harder and faster to get me off or get down on all fours so I could fuck him doggy style and really drill my cock into him fast and deep. One day I was giving it to him in his basement and his nephew came down the steps quietly and I turned my head and saw him watching us. He asked us what we were doing, and my boyfriend said We're exercising, now get outta here!" From that point on we started renting a hotel room every couple of weeks for a night or 2 and would spend the whole time having sex and having orgasm after orgasm. It was like he was a nymphomaniac sex machine when he was on Ritalin, he just couldn't get enough cock or cum in his ass to satisfy his sexual urges and desires. Like I said it could take me a long time to have an orgasm is specially if I was on ritalin and drunk, but he could cum in a couple minutes, (especially if he was being fucked) so he would have probably a good 5 or 6 orgasms before I even had one. And he would also turn into a sexually deviant, dirty, freaky slut that just wanted to be used and degraded. The filthier, the better. We started off as friends that would occasionally beat off together, but a few months later I was giving him facials, golden showers, fucking him in a hang on the door sex sling, and tieing his arms and legs to the bed. I shot so many loads of cum in his ass in a row one time and I had just climaxed again and was totally spent. A few minutes later he starts sucking my cock as I was napping and when I was hard he mounted me and slid his ass onto my cock and semen was oozing all over me and the bed because he was completely filled to the brim with cum. Every time he word ride to the top of my dick and then slide down, more and more of my baby batter would squirt out the sides of his asshole. I literally was fucking him with my semen as lube.