Part 1
—The song that Bon Bon sings is based off of "The Candy Man Can" from Willy Wonka and the Chocolate Factory, written by Leslie Bricusse and Anthony Newley and sung by Aubrey Woods.
—Lyra is known for her silly behavior in-show, so I came up with the idea that she's an insufferable jokester who always tells corny jokes that make Bon Bon laugh and everypony else groan (and follows up every punchline with "Get it?"). Part of her inspiration was Carlos from The Magic School Bus TV series.
—Twilight probably knows most of Ponyville's citizens fairly well, and it's implied that she knew Lyra prior to moving to Ponyville (as Lyra waved at her in the very first episode). It's my headcanon that they're fairly good friends.
—Of course Bon Bon and Lyra pick up on the feelings between Twilight and Flash right away.
—Da: Irish slang, "Dad." Ever since I saw this picture, it's been my headcanon that Lyra has Irish ancestry, so I gave her some Irish slang in her speech.
—I still follow the fan theory that Tootsie Flute is Lyra and Bon Bon's daughter, accepting the fanfiction And Tootsie Flute Makes Three as (mostly) canon in my universe.
—It's my headcanon that Amethyst "Sparkler" Star is Ponyville's premier fillysitter and a big sister figure to many of the fillies in town, including Dinky Do and Tootsie Flute.
—Sweetie Drops being Bon Bon's old name is a nod to Hasbro officially renaming Bon Bon as Sweetie Drops. I just think Bon Bon's a better name.

Part 2
—Small, but noteworthy list of unidentified criminals: while Phillip maintains that there's no such thing as "the perfect crime," even he has had bad luck or been outsmarted on occasion.
—Muleta: ponyfied version of Malta.
—gobdaws: Irish slang, "idiots."
—Lyra is good at playing on other ponies emotions to get them to do what she wants; her pouty face is nearly irresistible.
—sound friend: Irish slang, "good friend."
—Did you know that there's a branch of forensics related to typewriters?

Part 3
—Phillip gets a crime sense warning that leads the group to Bon Bon's.
—We get another demonstration of Phillip's parkour skills. He's the kind of pony who likes to take the direct route, especially when he knows that the situation is urgent. Roads? Who needs roads? I've got rooftops.
—My headcanon is that Bon Bon has a short fuse and curses like a sailor when she's mad, although she's careful never to swear when there's a child nearby.
—He hated that look: because he's been there, and knows how it feels.
—cowering a little as her wife's rage washed over her: Lyra has been on the receiving end of Bon Bon's anger more than once.
—Detrot: ponyfied version of Detroit.

Part 4
—"Don't "Princess me": when Twilight's focused on a job, nothing's going to stop her, not even her title and position.
—Flash's examination of Dreamcaster demonstrates his observation and deductive skills, which are comparable to Phillip's.
—I actually had to do some research on how combination locks worked for this chapter.

Part 5
—Lyra's distinctive, unusual way of sitting: a reference to the episode Dragonshy, which had Lyra sitting like a human on a bench. It's my headcanon that she just does this to be weird.
—fillyfooler: a common name in MLP fanwork that's used as an insulting name for a lesbian.

Part 6
—"fair play": Irish slang, "well done!"
—"Gimme five!": a nod to the common "Lyra is obsessed with hands/humans" meme, which I don't particularly follow.
—Phillip isn't good with young children: not because he dislikes them per se, but because he doesn't know what to do with them.
—Colcannon: traditional Irish meal, made from mashed potatoes mixed with cabbage or kale.
—Flash gets this promotion for his skill and duty.

Author's Notes:

Chapter notes from the story.