The cat actor who played the stray cat is named Lala.
If you go upstairs in the bar in The Slums, there's a bowl filled with liquid and what looks like RAM blocks. This is likely a pun on Ramen soup (RAM-in-soup).
There is a Persona 5 reference where you enter Midtown, you can find a robot named 'Sojiro' and he would state that he "used to own a bar." Sojiro in Persona 5 did own a bar, technically a café, called Leblanc.