He wasn't sure whether to file away the first bit of information into the general knowledge for life or things to remember about Greengrass in his mental file folders, so he did both. Valerian was criminally uninformed about ghouls, ghosts, and anything else he would have learned about if he would have broadened his horizons at Hogwarts, where he'd spent most of his time treating his studies like pre-hospital training.

He took  sip of his drink at the same time Greengrass did, subconsciously mirroring his body language, and smiled from behind his glass when Greengrass launched into his questions about boggarts, as if he enjoyed them. Of course, a Ministry official who dealt in banishing ghosts (or talking to them?) probably had opinions on other sorts of creatures that lurked in homes, but to be "great" with boggarts seemed... well, if anything, it was particularly useful in this scenario.

"It is," he said, trying not to look too pleased with the turn of events. Would it be odd to ask him if he could assist him in ridding of it? His mind began to jump to other thoughts, too - namely Greengrass standing in the middle of the attic, looking all-too focused on his task and giving Valerian the opportunity to let his eyes linger a little longer. And below him, his bedroom -

He cast the thought out of his head, because it was a ridiculous one to be having but unfortunately not an uncommon one for him.

"And if you'll help me rid of it I'll owe you a favor," he offered, his brows raising in expectantly.

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