You spend a few seconds experimenting with magic, seeing if it works here and If you can just imagine things. You try picturing a flower and it appears in your hand, which answers that question. Although you get the feeling that things you do in here could have an effect on the real world (although, maybe not the flower) and that the only reason you can do it without resistance is because your other self lets you. You give the flower to your other self and ask "Do you want to play a game?"
Your other self gives you a hug and says "I would love to, but there is so many games to play. What do you want to play?"
You decide to play some chess, although you win again and again. Your other self tends to act on emotion and not think things through, but you are the opposite. You talk with her and learn some things. She actually thinks Voldemort's Horcruxes taste delicious and would like some more, she is also very cheerful and happy. Like you, she seems to have no sense of morality and is happy playing games or killing enemies. She also enjoys playing games, but it doesn't matter which one and she hid deep inside your soul while you were in Azkaban, so the Dementors couldn't affect her. You also come to several insights while talking to her.
You are more of the outer-self, while she is more of the inner-self, although there is a bit of mixing, and you are dominate in most of your soul, although your other self controls the heart because the heart is the source of emotions and she is your emotional side, while you are the coolly logical side. If it ever came to a battle for dominance between you, you aren't sure who would win, as the heart is the source of much of your power. Luckily for you, she is quite happy being primarily the inner-self and wouldn't fight you unless provoked. After all, if you are gone who could she play with?
Eventually, it is time for you to wake up, you can't stay forever. You say goodbye to Inner and leave your meditative trance.
[] What do you do now?
[Trait Discovered: Twin Selves]
A.N. Your inner self has actually influenced you before, both the pranks and the hug you gave yourself were her influence.