Keep him chastity for a week, then bring another couple with a dominant female and a sissy hubby and make him make the other sissy cum before he can be released. Alternatively you can have them both blindfolded and tied up so they can't physically move and then released from chastity...then have each women hand milk the other's sissy and whoever comes first will be forced to suck the other sissy until he cums.
This is a fun game to play with another couple that has a dominant woman and a sissy husband in chastity. It's got a very humiliating twist to it, and both women can enjoy and join in on the spirit of the competition.
Both women need to clearly explain the rules to their sissy husbands before blindfolding them and making it so they cannot hear or see. They should tease each other's sissy boys and remark about how much more of a sissy each one is. They should provide constant dialogue and teasing, and they should film the whole process to watch later in the night.
The two women should dress normally, but as sexy as possible in order to provoke and tease the other's sissy boy. Each women should dress their sissy boy as they want ahead of the evening. Both women should keep the key of the other woman's sissy's chastity device on a necklace around their neck.
This should be planned well in advance with a likeminded couple. You should agree to keep each other's sissy in chastity for the same amount of days prior to the event in anticipation of the evening. You can make a nice evening out of it at home with another couple, and the two sissies serving and cooking for them until the grand moment of truth (and fun).
Make sure it's planned well in advance, and that you involve a nice, fun, young, and most of all…really attractive couple.