The only thing I remember at this point is when Lynn Stewart-Pierce brought it up to Will Harper at the Allen home in "Home Fires" before the 7 minute mark. Lynn said "So speaking of your transparent living arrangements, what's the deal with you and Artemis?" to which Will replies "What? Deal? No deal! There's no deal. I mean I'm grateful for help with Lian, but don't get the wrong idea." then Lynn retorts "Really? You're both single, living in the same house... but sorry, I shouldn't make assumptions." Will "Yeah...no."Which episode was that Nightwing line in where he brings up the Will/Artemis thing, does anyone remember? I need to go back and watch it again to get a better read on it.
I don't recall Dick ever insinuating anything about them.