Yeah there has been nothing really as you say, not even a sniff on the dom path (Kiyomi does have a lot of interaction with SubKane but it is mostly with Olivia as well who is getting closer to her).
I'm very curious how the dom romance will actually start and develop given there is nothing really at the moment. We're getting a little late to be starting romances with people we've not had a great deal of interaction with. However, all that being said, she is only a T2 unfortunately like our beloved red haired wastelander, so maybe we are expecting/hoping for too much given Tess has already said only the T1's will get proper romance paths.
Would seem there is no 'official sub romance' for her, as those are reserved for Olivia, Vero, Junko and Claudia (last I read)...and she says no 'love'...seems like it might be a more respectful intimite path where she doesn't love you but doesn't demean you either and treats you well?