Well not every planned Arch Type will have you dominating them, Boozer Diane is an example. She mostly has scenes in which she dominates you except one scene that needs a special trigger and topic needed.
I agree that a corruption tagg is needed....actually now that I think about it, a lot of tags are missing that could be added.
Because of the way the conversation mechanic works I think all AT's are a form of domination.
Essentially, you figure out how to change people. You talk about things they like, while working in topics that will corrupt them into changing their behavior.
Once you have spent enough time manipulating them, then you literally force them to change.
No one in the game chooses to change on their own. Everything that happens is directly related to active manipulation on the player's part. The game mechanic is literally simulating mental domination and manipulation.
I don't see how this can be seen as anything less than some sort of mental domination.
As the player you literally plan out your manipulation. You figure out what you need to do, and then you set about putting it into action. It is pretty dark if you really think about it.
In most VNs you have some choices to make, but you don't necessarily know what the outcome will be. In Loser you actually strategize the best method to implement these changes. The corruption in Loser is player driven in a very tangible way.