Lucifer was always serious and stern. Never laughing much and never showing alot of emotion but in this moment, Lucifer was struggling to keep in a laugh. You two were jn public with Diavolo, Diavolo was in the restroom and you and Lucifer were standing outside the restrooms waiting for Diavolo to come back when a child tripped and fell face first, causing Lucifer to almost accidentally laugh, his face turning red as he struggled to hold back a laugh before finally doubling over holding his stomach as he laughed his heart out, laughing as if he were a kid again.