(This was all just an elaborate ruse to draw Susan in a cool outfit; and to include my headcanon that Angel Dust is the only person at the hotel that Susan likes)
She calls him Albert and still has no idea that it's not his name. He has told her numerous times.
She (badly) eavesdrops on his conversations and relays what she mishears to large crowds.
"I heard him say he wants to marry that nice television boy." - Susan 2024
Susan likes to imply that Alastor is, in fact, an awful, modern young man with his radios and his walker talkers.
She cannot pronounce microphone and Alastor thinks it's a personal attack at this point. Sometimes she calls it a microwave while making direct eye contact.
Susan has never listened to any music past 1899 and believes Jazz is the devil's music (and not in the good way). Gramophones are the only acceptable at-home listening experience.
She likes to tell Rosie that Alastor is trouble. This is true, but still offensive.
When told he was a deer demon, Susan countered that Alastor wasn't nearly pretty enough for that.
Susan is the only demon who has managed to fully derail one of Alastor's broadcasts when he did a special live show in Cannibal Town.
Vox didn't let him live it down for 10 years and Rosie likes to refer back to his semi-hysterical, anti-Susan tirade as "inspired and honestly a delight to hear"