Your post is so wrong I don't know where to begin. Eva and Sasha was not a one night event they were alone in the bedroom and apartment for several nights. I will agree with you that with the new guest girl he and she were crossing the line, however he didn't fuck her. There was also the belief that they both were under the influence of more than alcohol, still not a good excuse.
Masha did this to herself, she treated Sasha with total disrespect both times that TK was over. They would sneak in the bathroom and have oral sex on more than one time. Masha at many parties would chase around guys and often take them into the bathroom with out a camera. Sasha would have to chase the out of the bathroom on many occasions. Masha never really showed any respect for Sasha.
If TK or Dick really respected TKG or Jane why is he trying to fuck any girl that comes into their apartment. Much more of an asshole than Sasha.
Dasha didn't steal Sasha, Masha gave him away with her attitude towards Sasha. I am just surprised it took so long. Masha is only concerned with herself. What is commonly called a self center bitch. JMO