Urk...!
HOLD IT!
I'm sorry, but...
...there's a contradiction in your testimony!
You say Dave would be okay with Chester inviting men into his house. But...
what if it was, say, the main character who he invited over?
Well then honestly, that's down to both of their personal preferences. Dave could decide to allow or not allow Eddy to hook up with Chester, and he could have any number of reasons for this decision.
And Chester himself may not even want to hook up with Eddy. He doesn't seem thrilled about relationships in the workplace (although it's unclear if he meant in general or specifically with Pat).
I loved this whole thread, but I'm sorry to say, but...
OBJECTION!
If Chester and Dave are in an open relationship, then what's stopping Eddy from going after both Chester and Dave? If we're adding the meta knowledge from the first one, then you can only go after one of them. What's stopping them from continuing in with the idea of Chester cheating on Dave idea they set up?