Outwardly cheerful and optimistic, Mel often encourages Chinatsu during battles. This demeanor gradually reveals manipulative tendencies, particularly in how she influences Chinatsu's decisions, stemming from being shaped by Chinatsu's perception of Suzuko as cunning. Mel uses phrases like "you'd look weak if you backed down" to sway Chinatsu, especially regarding erasing Suzuko or submitting Shohei's contract to the Bookmaker. She also exploits Chinatsu's loneliness by positioning herself as her only friend to reinforce her influence.

Mel's existence is directly tied to Chinatsu and Suzuko's past. She is based on a green plushie crafted by Chinatsu as a symbol of their friendship; Suzuko named this plushie "Mel" (and a matching red one "Ril"). This plushie inspired Mel's LRIG form. During battles, Mel struggles to convey the critical stakes of the Selector battles to Chinatsu, contributing to early losses. She repeatedly urges Chinatsu to use her "Berserk" ability by wagering coins, which Chinatsu initially refuses. Mel eventually compels her to do so by emphasizing the risk of losing everything otherwise.

In the card game, Mel embodies a defensive playstyle. Her abilities focus on boosting SIGNI power or granting immunity to effects, prioritizing field protection over aggression. Cards like Code Order Steak or Code Eat Curry represent her limited offensive options.

Mel persistently refers to Chinatsu as "Chi-chan," despite Chinatsu's objections and insistence that Mel "is not Suzu." This naming reflects her connection to Suzuko while highlighting friction in their dynamic. As Chinatsu's hostility toward Suzuko lessens, Mel's manipulative traits similarly diminish, indicating her personality is intrinsically linked to Chinatsu's emotional state.