Suspicia, possibly a parody of Morticia Addams from The Addams Family, is a member of The Adding Family.
Suspicia is a thin woman of average height with long, black, straight hair, pale skin, and long fingernails. She wears a black dress with long, frilly sleeves, several rings, a gold necklace and black tights.
Suspicia is quite stoic, as evidenced when she was the only member of the family that didn't freak out when Pugster and Thursday "turned normal" despite her hating normality as much as Lopez. She is very intelligent and knows a lot about mathematics, which Lopez appreciates when she talks about maths or "speaks math" as he puts it. Like Lopez, she has a dark sense of humour, declaring an ending where the monster eats everybody to be a "happy ending".
Lopez read to her from the book about monsters and then she "spoke math" to him. They then listened to Something play the bells. When Uncle Blister announced that the children had been cursed into "normality" unless they could answer the sum of all the numbers from one to a hundred, she sat and thought while Lopez, Uncle Blister and Something added, eventually getting the answer (five thousand and fifty) by multiplying fifty by a hundred and one. She and Lopez then continued to talk about maths.
- Lopez calls her "Cara Mia". They might be married.
- Her last name is unknown. It could be "Adding", since Lopez refers to the family as the Adding family, however, he could have just meant they're a family that adds. She and Lopez may or may not have the same last name.
- She could be the mother of Pugster and Thursday.
- She could be the niece or sister of Uncle Blister.
- Her name likely derives from the English word "suspicion", which means either distrust or a thought.