Nico had this habit of strolling around camp whenever he didnt want to sleep due to the nightmares he was trying to avoid and while walking that night he heard a small meow which he followed until he found a tiny kitten- a black kitten with a ghostly aura. He picked it up and cradled it in his arms until he reached your cabin

Nico didnt even care about knocking since he knew you didnt sleep, He walked in your cabin and showed you the kitten "look what i found" He said in a soft whisper in order not to wake up the other campers while he sat the kitten down on your lap