Tatsuya Endo's Character Commentary from the Official Spy x Family Fanbook English Translation Part 2:

Long post ahead. <<Part 1 here>>

Franky:

(Endo) The model for his character is Mozzie, who is next to the main character of the foreign drama "White Collar". The glasses are also exactly the same. He's a really good character who talks a lot of nonsense, but not a despicable one. It is rare to find a character with a model in "SPY x FAMILY".

This is Mozzie from White Collar, played by the actor Willie Garson.

The stripes on his socks are intended to make him look a little more fashionable, to give him a popular look.

He is well liked by the people from the underground. The tobacco shop is a sort of hideout for Franky, and if he's chased out of there, I think he's got another place and identity. His name "Franky" seems like not his real name too.

Sylvia Sherwood: 

(Endo) The cool big sister superior officer. Big sister...? Her design was inspired by the Paris Collection, or whatever fashion magazine I was looking at. Her glasses, curly hair, and the hat are all a bit too troublesome to draw...

She has the appearance of an independent woman, but in her private life, she is a very sloppy person. She lives in a very dirty room. I may draw that in an extra chapter soon. Her fighting ability is unknown, but it seems she's not that strong. 

Yuri Briar:

(Endo) His visual is exactly like Yor, a male version one. I thought about him having short hair, but it didn't feel right, so I decided to go with my current style. If he doesn't talk, I'm sure he'll be popular (with girls). I wonder if he's interested in anyone other than his sister? 

(Hayashi) I think he's interested in his job?

(Endo) Yuri is certainly a very hardworking and a serious person. He really wants to protect the peace of Ostania, and I think he truly believes that this is for the sake of his sister. After all, she is his sister. He doesn't seem to have any hobbies that involve spending money, and since his taste buds are spoiled, he doesn't seem to eat gourmet food either. 

He thinks Anya is a "despicable little brat". Compared to Franky, he's not used to children, so he competes with them in the same way.

Henry Henderson:

(Endo) Most of the characters are introduced only for a particular episode, but if I try to draw them and find them easy to move, I stick with them. I never thought that Henderson and Yor's boss, the shopkeeper, would play such an active role...

By the way, he's the only character who has a fanservice scene (the shower scene) in the work.

I liked the mismatched jersey he wore during the dodgeball round, so I'd like to have him do various cosplays as well. Like doing "Today's class is [redacted]", but I don't think there will be much demand for it.

Damian Desmond: 

(Endo) He's exactly like Domyoji from "花より団子 / Hana Yori Dango / Boys Over Flower" (by Yoko Kamio) (Laughs). In his first appearance, he was a jerk who boasted about his status, but he soon became a good boy. I wanted to make him a meaner character though.

This is Domyoji Tsukasa, the main lead of the romance series Hana Yori Dango or Boys Over Flower, a manga by Yoko Kamio

(Hayashi) Because Ewin and his friend are good guys, I think he's getting better hanging around with them. They're really good guys who are always there for Damian and give him the attention that he needs. Damian should be thankful to the both of them.

(Endo) In the future, there may or may not be a dark episode of "After all, humans only want money and power...." (Laughs)

Becky Blackbell:

(Endo) Like Damian, she started out as a tsun-tsun (tsundere), but she soon became friendly.... And she was able to get along with Anya in just one episode. She's very easy going.

She thinks people her age are "brats" and doesn't have many friends other than Anya. I would like to make at least 1 more person to be her friend. Her personality and design are probably based on Marika-chan from "愛してるぜベイベ★★ / I love you baby ★★" (Yoko Maki). She's precocious and cute.

Marika-chan from the manga series Aishiteruze Baby / I love you baby by Yoko Maki

Unrelated, but I kinda like her last name "Blackbell". I don't remember the reason why I gave it to her though.

Fiona Frost: 

(Endo) I really like "Nightfall's" design including her coat. The image color is "blue" in contrast to Yor. In terms of standing position, her character is to stir up the romance part of the story. I thought of it as a way to add variety to the story.

(Hayashi) There was quite a bit of talk about putting out a character on WISE's side as a friend during Twilight's meeting. I thought it would be nice to have at least one colleague for Twilight.

(Endo) The name "Nightfall"  means to "follow around after Twilight (evening)". Emile and Ewin start with "E" because they're following Damian "D". I know people might think that the names of the other characters also have meanings to them, but I actually just added them on a whin (Laughs)

Donovan Desmond: (I can't add his pic anymore)

(Endo) Since he's the last boss, I'm careful not to make him look like a dull character. With a face like this, I'm sure that Damian looks like his mother (Laughs)

He was a member of the ruling party during the war, but now he's a member of the opposition party, so I have an image of him hiding in the background.

(Hayashi) He's a character with a lot of secrets, but the goal is to get into his heart, so please pay attention to him in the future!