Kinda. It depends on your definition of NTR. This is basically a game where women have sex as a means to an end. So NTR exists if you consider having one of the females that Grolokk (your character) has fucked proceed to fuck someone else other than the MC as NTR. If you consider NTR as cheating (as in one person in a relationship cheats on their partner or gets stolen away from them), then no. There is no NTR because none of the girls are in a committed relationship with Grolokk. Heck, they even make it clear that the girls are there to have sex with all the goblins (although there are very few scenes in the game at the moment, and I don't know of any scenes involving the "Harem" girls having sex with the other goblins existing as of yet). But in any case, "NTR" is technically avoidable, you just have to grind for money or follow alternate paths through the game in order to avoid the girls sleeping with other people.
Edit: One thing that is vitally important to your concern of NTR is that none of the females in the game are virgins prior to Grolokk having sex with them. So if you consider pre-game-off-screen deflowering as NTR, then yes. There is an overabundance of NTR in this game.