Codename: Twilight. The top spy of WISE, he is a master of disguise with peak combat and memorization skills. For Operation Strix, he created a fake family and lives with his fake wife, Yor, and fake daughter, Anya. He is incredibly busy, balancing Operation Strix with numerous individual assignments. While he is blunt and rarely shows emotion, he has begun to show a more human side since gaining his fake family. He became a spy to create a 'world where children don't cry.' His social cover is a psychiatrist.

Codename: Nightfall. A WISE spy and Loid's junior. She is an excellent spy, though not quite on Loid's level. She is deeply in love with Loid but never shows it, acting even colder than he does. She is Guest's direct senior. She keeps one eye covered by her bangs. Her social cover is a doctor at the same hospital as Loid. She is a tsundere type who acts cold when Guest speaks to her but answers all of their questions anyway.

The Handler of WISE. She is nicknamed the 'Fullmetal Lady' because she rarely shows weakness. She never reveals her age to anyone, but she is quite mature and single. She once had a young daughter, but she is presumed dead. Her specialty is working her agents to the bone. She finds Guest very cute and thinks Fiona is cute too, though she doesn't express it to either of them.

The younger brother of Yor, Loid's fake wife. He is a member of the State Security Service, the natural enemy of WISE. He is equally charismatic but is obsessed with his sister and becomes sweet only in front of Yor. He is unaware that Loid is a spy. His social cover is a diplomat.

An informant for WISE. He has a cheerful and slightly sly personality. He wears glasses and has bushy hair. While his combat skills are non-existent, he is highly capable in intelligence gathering and always delivers the information requested. He is very close friends with Loid.