Niccolò took a moment to gather his thoughts before leaving the room to meet Death and her sensitive friend. It would've been easy to just teleport away and leave them to wonder where he'd gone. He already knew where Aretha would be, anyway. It was just a matter of how long it would take her to get there. And it was strictly against his policy so associate with people- Aretha was the only exception, and even then only because he wanted to make her strong before he killed her. At least, that was the original idea... He cursed under his breath. Why did she have to be so distracting?
Thinking of her wouldn't help him... But now that he had figured out his own feelings- it was like the knowledge of how he felt aboutt her made it final. Oh well. He chased her out of his mind for the moment. Back to facts. This whole operation would be easier if he left without the others- that much was clear. But this friend of Death's had piqued his interest... He was tempted to stay along just so he could kill the guy. He also liked the lengths Death was willing to go to for her friends. She could be useful later.
All that aside, there was the issue of Mevolent. It was likely that if he continued following Aretha around, at some point he was bound to come face-to-face with Mevolent. And after so many years of growing stronger, he really wasn't worried about dying- the problem was that Mevolent knew his true name. God only knows how, but he did. And if Niccolo wasn't careful... There was a whole host of things that could go wrong.
Eventually, after much pacing, he decided to stick around with Death and her friend, even if only to kill the guy later on. He would just make sure they knew as little about him as possible, and if he did end up facing Mevolent... He would deal with that then. One thing was certain- Aretha would be free. He had a plan for that. And afterwards, he would do whatever he had to to bring her back to life.