The only couples who are sexual partners are Alina&Anton, Leora&Paul and Diana&Efim, all the others are not.
I don't know what relationship they have but there is no sexual tension or interest. >:(
I don't know what they do during their day, but when they come home they just want to sleep, watch television or connect to internet, which is absolutely fine but for us is terribly boring and they should be out of RLC.
RLC must have realized that with Sofia and Katya made a mistake and they had finally found a good couple: Diana&Efim, or maybe it was just luck. I hope the new couple will be worth Diana&Efim, but... ???