We call a person/act/etc. that manipulates a manipulative person/act/etc.
Now I want to talk about a person who is manipulative and I want to say that she has a flaw which is that she is manipulative. I cannot say a manipulative flaw because that would mean the flaw manipulates itself. So how can I describe the flaw. I want one single word.
Personally, it seems to me that manipulational is the best option but I found that it has been used very rarely.
The/a manipulational flaw: a flaw because of being manipulative.
Compare for example communicative and communicational. A person is communicative who communicates well. So that person has communicational skills, skills related to communication.