(I apologize for how long it took me to write this response! If it ever seems like I forgot, Just bump it and I'll respond!)
Pierce could tell that Auraelous was interested in his book. He hid his smile and leaned back, the seed was planted and all he needed to do now was let the glorious plant come to fruition. "Well, some in the underworld like to call me the Mad Hatter of Amsterdam. Why Amsterdam I don't know, I've never even been there. Or have I?" He winked and sat up straight, his lunch had arrived and he needed to leave a good impression on the waitress if he intended to leave here with more than a satisfied stomach.
Seeing the other man's reactions to his playful name-calling excited Pierce like a child who got exactly what they wanted on Christmas day. He made a mental note of this and set a goal to irk the man with as many names as he could in the future. It wasn't his reaction to the name that caught his attention, however, it was how panicked he became after hearing that simple sentence. Pierce frowned slightly and laced his fingers together. "A brother?" he said quietly. He watched as Auraeleous sped out of his seat and ran out. Did he miss something?
A quick perusal of his book gave him all the information he needed. Matteo had mentioned things spicing up at the Agency a few months back. He had said something about a small fry on his way to becoming a bigger fish in the water. The name was slipping him but within a few more skimmed pages, the name was there. Pierce felt gratitude for his obsessive note-taking because, without them, he wouldn't have this much information to look back at. Nor would he have the rage he felt currently.
Matteo had always been a calculating person but the person he apparently trusted the most, was Pierce. This was laughable considering what Pierce had been planning for him. There was a reason he was not solely affiliated with his business, why he preferred to be a contract killer. Yes, he mainly signed with Matteo but that didn't mean he didn't have business elsewhere. It was why Pierce felt so angry at his cowardly use of a scared lost soul who was only trying to protect his loved ones. It totally wasn't because Conan reminded Pierce of his past life. Matteo had irked the Panther and its claws were coming out.