This dialogue is so forced the characters should denounce the writer for rape.
Really too twisted in one direction.
MC simply had to say that his skill reinforces others and can't be used out of dungeons, and if he could do so he would have already put them under his control, but instead is like he finds trying to have a normal life by speaking for 30 seconds too tiring.
There were other ways to frame MC in a negative light, like making the taming have some visual effect like chains or something, MC could have just lied about it fromthe get go and said it was a max support buff he could only use on one person, no reason to be honest abut it, braindead.