If someone were to learn a forbidden/exclusive jutsu, do you think that someone (maybe Yamanaka) would try to erase it from their memory? I kind of want someone from the main Hyuuga clan to teach an OC of mine Twin Lion Fists, and is given a seal as a consequence. Would they try to remove the jutsu from my OC's mind? Could you give me some tips on writing this particular part?
The user changes the shape of chakra released from both hands into large guardian lion-shaped shrouds. Doing so greatly increases range and destructive power. The lion heads drain the chakra network of those they touch. It is an extremely difficult ability to learn, as the slightest mistake in chakra control will lead to failure, meaning it is a feat requiring the Byakugan.
As such, your OC wouldn’t be able to learn twin lion fists without being a Hyuuga. I get the impression your OC isn’t a Hyuuga though.
Naruto stole a scroll and learnt the multiple shadow clone jutsu without any noticeable repercussions despite it being a forbidden jutsu. High level jutsu also take a lot of time to learn, so it seems likely that they would be found out while they are learning the jutsu rather than after. I can’t think of any memory erasing jutsu in the manga, though it seems there are two possible jutsu in the anime, and one in a film. None of them were used by a Yamanaka, so I don’t even know if they’d be capable of it. Therefore, I’m not sure a Yamanaka would be able to do such a thing even if they wanted to, and I’m not sure if they’d interfere in Hyuuga matters. Considering the seal branch members already have, I imagine that they would be allowed to seal away a memory of one of their own (but not from someone outside the clan) if they were capable of doing so.
If your OC learnt a forbidden technique then I don’t think that there would be any repercussions. As for an exclusive/hiden technique, I don’t think that anything would be done if the OC is part of the same village (but not clan) as the clan involved would not have ‘control’ of the OC, though the hokage would. If a character from a different village learnt such a jutsu though the hokage may send out a team to deal with said character in the interests of keeping those jutsu within the village.
