Can Thomas talk/send images/send notions into your character's mind? Yes. Regarding notions/ideas: Crane's mentally aware of his own character. He's a psychiatrist, after all. He might notions to intrusive thoughts or something intellectual like that.
Can Thomas poke around in your character's head/explore beyond just communication? Go for it.
To what extent is it cool for Thomas to explore you dude's brainpan? I'd say up to the middle. Crane's scientific, analytical, curious in nature, and enjoys learning what makes people tick. Anything deeper? It's some damn scary stuff. I think Crane's closely-guarding everything like that, on the personal side. If he finds out he'll lead Thomas into places he doesn't want to go. He'd REALLY hide the stuff with his great-grandmother.
What kind of stuff would be cool to Thomas to dig up, if he spends more time snooping in your character's head? General mood. He can't feel scared, so he's really frustrated over that. I'd also say that Crane's mental state is worse than he's letting on - he's got a good poker face. I'm quite open to other things too, as long as we can plan them out ahead of time.
What stuff do you NOT want Thomas digging up in your character's head? Anything that'd flagrantly out Crane as a villain. There's some stuff building up and I'd like to take my time with it. Things that'd ruin his plans or threads with other characters without discussing it first.
Do you want to do any kind of bleed over thoughts/feelings/memories if Thomas is flipping his shit while mentally connected? If we can figure something out! Though I think Crane'd keep his own feelings, since he has a psychological problem with feeling no fear, etc. It feels quite ingrained due to his childhood. Also this'd be something he'd use, just sayin.
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