I assume not according to the way this site defines NTR. In other words neither Ryan or Oliver are going to get jealous by whatever Grace gets up to. Ryan only appears to be concerned about whether his wife's involvement in Oliver's activities can help him become richer, whereas Oliver just wants to prove his belief, that all women ( even someone as seemingly pure as Grace ) are basically whores if given the necessary temptations. They're both using Grace in some way, neither of them appear to have any real romantic interest in her, and therefore the usual definition of NTR doesn't really apply?
I really don't like NTR games for two reasons:
1. PoV - in 99% of cases it is played from the perspective of the husband/boyfriend who is weak - he sees someone harassing/fucking his wife, but he doesn't do anything, he just whines
2. fmc's corruption is in the form of coercion/blackmail, fmc is forced (against her will) into corruption and sex. This is very close to the definition of rape.
However here we have a very different approach. Neither the MC (Ryan) is weak, nor the FMC (Grace), against her will, is forced into corruption. Corruption is carried out by provoking the fmc's ego to be more sexually daring. And best of all, there is a plan that in the end fmc (or her husband - which would be an even better variant) will take revenge on those who sent her to debauchery. I don't remember a game where a female character takes revenge on those who made her a slut/whore.
I don't know what I expect more: when they finally break Grace and send her to debauchery, or when she starts to take revenge on them.
It has definitely become my favorite game.