The End Goal

It can be any of those things and it can lead to anything you want it to. Whatever the two of you want to evolve your relationship into is OK. The things you mentioned are just fine for some people and sound utterly horrible for others.

Chastity is unquestionably D/S since someone holds the key and someone is locked but it can simply be play. Make it what you find right for your relationship. I want Kevin to evolve to be less needy around sex, I want him to be more thoughtful, more conversational but I have zero intention of feminizing him. We haven't embarked on anything around cuckolding but we've discussed it. It might be in our future but not any time soon.

I don't necessarily believe in a slippery slope, at the end of the day you have two partners and both want to have the most fulfilling relationship possible. The cage is merely there to help remind him that HE is in charge of his behavior, not his penis. 

BDSM isn't a bad thing for many people. We don't choose to go down that path and that is perfectly fine. What sort of feelings or fears go through your mind when you are locked? Does being locked make you feel insecure about how far she might take it?

I don't think I have any fears when locked.    Quite the contrary actually, and would describe it as a very comfortable happy horny.   There are no spikes in my cage, and when I start to get hard it never really hurts.   It is more like my girlfriend is squeezing my cock, which feels good.   Although, I have never gone more than a week locked.    I would feel insecure if she wanted to take it further into stuff like cuckolding, cross dressing, or a never ending chore list while she sat on the sofa and ate Bon Bon's.    I don't see her every wanting this, but it would be a WTF moment, if it ever arose.    

That's a good point. WTF moments are typically triggered by extreme changes in behavior. If she eased you in to some of the things that you noted, you probably wouldn't have that knee jerk reatction. While I agree on cuckolding and cross dressing, I think she could probably ease you into the chore list and even possibly feeding her bon bons while you vacuum and scrub the floors. ?

This is a fear I have as well. Although I don't think chastity has to evolve into any of those things the fact is that there seems to be a strong connection. If you search about people practicing chastity those things are very often included. I have also read some blogs where you see posts or comments from a while back and they don't want anything to do with these kinks but in later posts/comments they are now practicing it. So the slippery slope I think can be very real.

Overall. Pursuing this fantasy may not be worth the risks. If my girlfriend told me she would want to indulge in things like cuckolding or feminization it would make me very uncomfortable.

You always have to take into consideration only a small subset of practitioners actually comment. There’s not a “right” way. There is what works for the couple. Period.  Just because there are multiple commenters does not mean a thing. 

I agree with what patches said and I do know numerous couples who have practiced basic orgasm control/chastity and it has never progressed beyond just that. We go a bit further with pegging and spanking but everything is optional, set boundaries, communicate and never go beyond the comfort zone that you both define.

by accepting chastity, the idea of his penis not being his main focus opens him up to other ideas. bluntly, is he interested in receiving anal? Are you interested in pegging?

Like you, Emma, it doesn't go much beyond control/chastity for us, with the recent introduction of some spanking. Anything else, well, not sure that will happen. We have to agree on boundaries and it does stimulate lots of conversation and discussion to stay within our own personal comfort zones....mostly (spanking notwithstanding). LOL