You are in luck, Cape Town has a decent amount of groups all around. Here is my glimpse into it:
1. Club Infinity Cape Town - is a fetish club and hosts swinging parties almost every month (the last one was on 8 Oct). The nice thing is that you will probably know lots of fetish/ kink people already who attend. Awesome parties.
2. Lisa's Lounge in Tableview is the longest-running swinging club in CPT ( to my knowledge), worth a visit.
3. Epi-cure is a new swinger venue in Hout Bay... they are hosting a picnic on 19 October. It will be my first visit, so I can not give you an opinion just yet
4. There's a party previously known as "Dome parties" that are generally every few months. It is by invitation only, so ask your friends to recommend you to the owners to get on the list. They have a lovely group of people.
5. Sandy Bay on the beach-worthy day - if nudism, sunshine, and the beach are more your thing then there are discreet spots for some naughtiness.
As with any community, as people get to know you then you will get invited to more events and private parties/plays. There are even more that I have not attended, so I am sure you will find a group/s that you enjoy.
I genuinely wish you love, joy, and toe-curling experiences.
Mr. GigglesZA