So Horny

I feel more sexually alive than ever in my life. I guess I'm just wondering does even short term SR increase arousal? And longer term SR lead to having a HFWO?

As to your first question, IMHO, YES semen retention (temporal abstinence) does increase ones's arousal quotient, please see the thread Aneros, Arousal & Abstinence.

As to your second question, that's a bit more complicated. I encourage you to read the 21 day challenge post for a little more perspective on this aspect of semen retention. Generally, there is a substantial drop in libido following an orgasm with ejaculation (refractory period). This is due to the release of various hormones in the body. Along with this release is a drop in blood serum testosterone which takes time to rebuild fully. This rebuilding may take from 7-10 days to peak and then dips a bit and stays relatively level until the next ejaculation. Prostate milking can also cause a similar decline to an ejaculation though the effect is shorter lived and not as severe.

So after the rebuild period substantial increases in physical arousal due to hormonal fluctuations aren't nearly as noticeable and this is where psychological factors weigh in heavily. Some men seem to be naturally wired to have HFWO's when highly aroused, some can have HFWO's through various training regimes, others (such as myself) can't seem to have HFWO's regardless of the strategies, including prolonged temporal abstinence. Where you fall in this range is probably a matter of genetic happenstance. In any case it is important to be satisfied with what your body gives you and don't let expectations or desired outcomes frustrate you when they don't manifest for you.
Good Vibes to You !

@philliephan I always like to be in SR because of the testosterone boost I get from it. I would also suggest as @rumel noted that you may want to try the 21-Day No Ejaculation Challenge and see how you progress with it. In the distance, you may want to explore "cock cages" (like the CB-series) or "chastity cups" (that I like to wear at night) to augment your experience with SR.

Hi @philliephan, perhaps you like to read about my experiences with a bit longer SR, and how it ended. :p
To give your "keyholder" some more hints, how to tease you and to increase your arousal even more, let her search for "ruined orgasm", for "femdom" and for "cum denial" on tumblr. It seems you will gonna love it. 😉

So following the advice of @rumel and @goldenboy to try longer SR I'm now on day 12. It has been something a little different for me. After I first posted this I wasn't as easily aroused for the next several days, but that all changed this morning. I woke up early today and felt like going for a ride. I started with my MGX-T and did nothing for for the first hour other than look around on Tumblr. I felt something start to stir so I turned off the computer and rolled over on my back and almost immediately the tool went to work. I had MMO's going in no time. After about 20 minutes I decided to give the PBI a try and OMG. The next 45 minute were pure bliss. I've only had 2 SO's ever and I had 3 today and another 2-3 that were really close to that level. I'm not sure if today was a true indication of what SR does for your sessions but god it was great.
@SOwithoutAneros I took your advice also and showed my girl what you said and she took that ball and ran with it. I'm now her new pet and we have been having a lot of fun with it. She sends me daily reminders that I'm under her control and if I cum without her consent that she will lock me up for a long time. She's already looking at cock cages if I happen to slip up. We are doing a Skype call on Sunday and I have to beg her to let me finally cum. Although after this mornings session I may want to wait a little longer.

Okay, @philliephan, lucky guy, if you like, here is another ball to run with - for you and your girl (or should I already name her keyholder?): I would recommend these hypnosis audio files, I first and foremost found very helpful for focus and relaxation and especially to learn letting go. They too are dealing with femdom, cum denial and jack-off instructions. Some of them might not meet everybody's taste, but keep in mind that there is a wide variety of different files to find*. Do only choose what you both really like. After all have fun! :p​
*Soundgasm.net provides a rich archive of Shibby's audio files, where you can get a short summary of every file and where you have direct access to all free files, there are even more on her patreon page.