5: The way he interacts with Trixie.
She walked into the dining room, the sound of hearty chuckles and breathless laughter like a symphony to her ear. "Nooo, Lucifer, that isn't how you paint a heart! It looks like this!" Trixie squealed as she put down the hand mirror and proceeded to paint a pink heart on his cheek. Her own cheek has a very anatomically correct heart painted onto it, complete with an aorta as well. She had a unicorn and some stars and several flowers, –and not to mention, the muscular organ that sustains our bodies with blood– sketched onto her face using the leftover face-paint from Halloween. Chloe could tell just how much love and care he put into the drawings, especially the stars, which a small part of her brain helpfully reminds her that he is the Lightbringer and so he should be able to properly paint their beauty, but the realism is astounding and the intricacy proves how much he cares.
"Ahh, Detective, come to join us?" He had much less detail in the drawings displayed proudly on his face; a rainbow, a smiling sun, the heart Trixie drew to prove what heart she meant, a cartoon devil, and what looked to be a crude cartoon of herself, everything covered in glitter and all the workings of Trixie.
"Nope, I don't feel like spending hours washing my face to get that stuff off. Sorry. Oh, and by the way, have fun helping Trixie wash it off her face!" And with that she spun on her heel with the intent of going to cook dinner. She only got a few steps away before Lucifer caught her arm.
"Wonderful of you to join us, Detective! Come sit, I don't bite." In a lowered voice so that Trixie wouldn't hear, "At least, not unless you are into that sort of thing, hmm?"
"In your dreams, Lucifer." With a roll of her eyes she sat down, joining them in their fun.
"Every night, Detective," He drawled, causing her to blush.
"Let's get to work, Lucifer!" Trixie called as she grabbed a brush.
Two hours later, Chloe Decker was covered in bright pink drawings and glitter, hair mused and cheeks hurting due to the amount of laughing she had done. "Okay, okay, that's enough. It's already 7:30, so let's just order a pizza." Laughing once more as both Lucifer and Trixie cheered because sometimes Lucifer is just like a child which is hilarious, she dialed the pizza place and sent in their orders.
They had grabbed some blankets and had crowded onto the couch, turning Moana on and enjoying their pizza. Lucifer expressed his displeasure with the movie quite vocally, however Chloe saw him wiping tears away when the grandmother died.
It was dark out and Trixie was fast asleep when she realized that she was pressed up against him –side to side– with her head resting on his shoulder. She felt so safe and warm… until he decided to move. She assumed she made a grumbling noise of protest since he replied: "Hush, love, I'm not going anywhere." Lucifer draped the blanket which had fallen as he shifted back onto them. "Good night, Chloe," He spoke in a softer tone and kissed the top of her head (something she would ponder over in the morning) and then she was out like a light.