KEL ASK 018 is a comic and an ask answer published in 2015 on tumblr by Kelly Green.
THE-PIZZA-DEMON: “I imagine 'Invisible Attic Piano Dude' just being totally over Cons-Hat's back and forth. Like, 'Come on guys, stop with the bickering already. I'm trying to play some sweet spooky jams over here.'”
In a one-panel, wordless comic, the Shadow Pianist is seen bringing a fruit basket in-between the Hatbox Ghost and Constance Hatchaway (who were apparently sulking in their respective corners of the Attic) to try to get them to stop bickering.
“See, he even brought you two a gift to make peace over! Now please get along.”