You've been asking questions involving the Saisiyat, so I'm guessing your question is about describing a tribal scarification ritual. It may not be inhumane to them. How about this for a rewrite? The scarification ritual involves cutting the skin on the face, and rubbing pine sap on the wounds, forming a permanent scar. To us, this appears cruel and inhumane, but to the Saisiyat [or whoever you're talking about], this is an important and necessary step in belonging to the tribe.

Umm, without the context I can't be sure. No problem with your sentence, and maybe you can also say The face in the process is carved by (a) knife and (is) put on some pine sap, so it is inhumanity. / so it is an inhumanistic behavior. I mean your sentence is all right, no problem at all.

Yes,it is an inhumanity behavior. Face is very important especially for a girl !

what is Q？ Sure cruel