Telepathy
First and foremost, this Pokemon is a seer of spirits. It can look into the spirit of the other Pokemon and grasp a move from it; there's no say as to whether or not CAP can actually talk to them.
As a possessive and friendly Pokemon, this CAP probably dreams of talking to its friends and strangers through the mind; thus, Telepathy.
That is, at least, my take on it. She doesn't have a mouth, so...