Killler7 felt it wasn't the right way to go for the game, and that's fine (Tanja pet route, I mean).
However, I want to point out that some people prefer this as their type of relationship. The way it seemed to me, when playing through it (I had a save for each a while back), was that Tanja was happy in the role. So even if it was a moment of weakness, and spite, that started the MC on the path, after realizing it was something she enjoyed I saw no reason to be guilty about it. That kind of relationship can be a loving one too. So I guess I didn't quite feel the same about it being wrong for the MC - but of course, Killer7 would know more about that than I would, being his creator.
However, I want to point out that some people prefer this as their type of relationship. The way it seemed to me, when playing through it (I had a save for each a while back), was that Tanja was happy in the role. So even if it was a moment of weakness, and spite, that started the MC on the path, after realizing it was something she enjoyed I saw no reason to be guilty about it. That kind of relationship can be a loving one too. So I guess I didn't quite feel the same about it being wrong for the MC - but of course, Killer7 would know more about that than I would, being his creator.