Kanon Toudou debuts as a main character in Pretty Rhythm Aurora Dream's twentieth episode, forming the unit Serenon with Serena Jounouchi. The unit later expands to Serenon with K upon Kaname Chris joining. Hailing from Kyoto, she resides there throughout the series. Her appearance features shoulder-length brown curly hair with distinctive coiled tips worn over each shoulder, golden brown eyes, and a fair complexion. In Dear My Future, her hair shortens slightly, thins out, and is worn completely behind her shoulders with loose curled strands, while her bangs become shorter to reveal more of her face [citation:].

Personality-wise, Kanon is sweet, tender, and elegant, serving as the reserved straight woman (tsukkomi) to Serena's exuberant funny woman (boke) in their manzai comedy. However, she exhibits intense possessiveness and jealousy concerning her older brother, Hibiki Toudou. This fuels a fierce rivalry with Rizumu Amamiya due to Rizumu's closeness to Hibiki, stemming from Kanon's obsessive desire to prevent his romantic relationships. Rizumu initially remains unaware of their sibling connection. Despite this flaw, Kanon demonstrates deep loyalty to Serena and prioritizes their partnership.

Her character develops across the series. In Aurora Dream, she gradually begins accepting space between herself and Hibiki, particularly regarding his interactions with Rizumu. By Dear My Future, she matures significantly, becoming more tolerant and referring to Rizumu as "Onee-sama" (elder sister) after Rizumu marries Hibiki. This evolution extends her family relationships to include Rizumu's relatives: Sonata Amamiya (mother-in-law), Ryutaro Amamiya (father-in-law), Kaname Amamiya (sister-in-law), and another unnamed sister-in-law.

Professionally, Kanon specializes in feminine-style fashion coordinates and Prism Show performances. Notable coords include her Summer Queen Cup outfit (Refreshing Marine One Piece, Vivid Carnation Sandals), casual wear (Platinum Dog Tag, Emerald Green Jacket), and performance attire such as the Melty Angel One Piece for Serenon and Silver Angel One Piece for Serenon with K in Dear My Future. Her Prism Jumps include collaborative techniques with Serena like "Hattrick Serve," "Prism Rainbow Hurricane," and "Smile-Smile Heart Dive Duet." After her original agency dissolves in Dear My Future, she and Serena join Pretty Top under Kyoko Asechi's management, continuing their manzai performances. A future vision depicts them evolving into a celebrated comedy duo.

Kanon's surname, Toudou, derives from "tou" (藤, wisteria) and "dou" (堂, temple).