Seems like your combination of the Erection Keeper and the Goodfella would work out fine. Another thing you may consider is combining a traditional harness with a feeldoe. The feeldoe can be worn anally (link) so you would get enough space between your front and back dicks.

I'd love to hear how it works out!

We have used this with the Fun Factory Tiger and she really enjoys it.

link


EF doesn't carry this, but we bought ours at a local shop. It is jelly, so a condom must be used.

I must add that we bought the Double Penetrator for our first foray in double penetration. I found it much too tight to be comfortable, and we soon bought a male harness, which we both prefer.

Now we use the Double Penetrator on another dildo for dp masturbation, as one does. She likes it because it has a flexible core, which can be adjusted to arrive at the most comfortable angle. It can also be moved up or down on the shaft of the other dildo to vary the depth of penetration.

My only worry about using this toy with another is that we may be violating the Geneva Arms Agreement, but it is a fun combination.