Explanation: Unlike everyone else you can change your body materia and transform into anything (e.g. an animal). This can be used in good purposes for infiltrating evil headcuarters or adjust your physical abilities by transforming and therefor do better in battle. If turned to the evil side, a transfomer could manipulate the "good guys" by looking like their loved ones and break them down.
As a person you are dissapointed with life. You have not so many interests anymore and has become depressed. Of course you can be happy, but your happiness subsides quickly and don't last very long. You isloate yourself from people since you think they would only hurt you, but some part just wants someone equal who understands the pain. When you transform it gives you freedom and you can be anything but yourself. You often pity yourself but don't let people come near and know what's going on with you. But the thought of opening up and risking being betrayed is too strong and intimidating to even try.
Negative aspects: You carry much hate to the world and yourself and in the long run this could lead to dangerous thoughts (suicide/cutting/killing) though the last one is least likeable since you would probably just have too much guilt.