Lucifer's deadpan, "I got better," in response to Chloe's puzzlement after he admits he really was killed is a subversion of the Unexplained Recovery trope: Lucifer is telling the literal truth, but it of course makes no sense to Chloe.
When Trixie tells Malcolm "I don't like you," he replies, "what's not to like?" This is a nod to the Pilot (2016), when Chloe tells Lucifer that she thinks Trixie likes him, and he replies, "of course she does, what's not to like?"
Lucifer says to Chloe "Reunited and it feels so good," which is a lyric from the 1977 Peaches and Herb hit "Reunited."
The title is said by Lucifer.