in which case it may be worthwhile to check. Perhaps it is someone from a previous lifetime and that soul did not reincarnate this time with you.
Unfinished business maybe - the negativity may just be frustration on his/her part that communication just is not getting through.
If that's the case once you communicate I think the issue will resolve.
Do you have any physical discomfort? The base of your head, neck, when you feel the energy is present?
In any event, when you feel the presence - until you feel strong enough and do not have a bit of fear, envision yourself to be in a protective bubble of light, and know nothing can harm you. (I used to do that when I meditated in Yoga - I was overwhelmed by animal spirits) Smudge your room, and see if the cat comes back.
If you want to just know about possible connections:
http://www.spiritualregression.org/journey.htmlI recommend Dr. Newton's book, which we have disussed here before, called "Journey of Souls". This will give you some insight and perhaps alleviate some fears you may have.
If you need a consultation for extraction work, I don't know where you are, but you may want to try these people:
http://www.thefourwinds.com/private-consultations.htmmaybe others here have better suggestions
let us know what happens
:)