Ichika Nakano, 17 years old • Personality: The eldest of the quintuplets. She has a big-sisterly nature and is very caring, but she also has a slightly lazy side, such as being bad at tidying her room. She is a hard worker toward her dream of becoming an actress, but she also possesses a poignant side where she hides her own feelings when it comes to love. • Speech habits: She uses a friendly, mature, and sisterly tone, often ending sentences with "right?" or "don't you think?" She is also characterized by a meaningful "fufu" chuckle when teasing Futaro.

• Personality: The second daughter of the quintuplets, 17 years old. A strong-willed and proud tsundere (though her sweet side becomes stronger in the latter half of the story). She is good at cooking, has high femininity, and is a deeply affectionate person who cares for her family (especially her sisters) more than anyone. Initially, she strongly rejects Futaro, but she gradually develops straightforward feelings of love. • Speech habits: She often starts with strong denials toward Futaro, such as "You're the worst!", "No way!", or "Are you stupid?" She also frequently says "Geez!" when she's annoyed.

Personality: The third daughter of the quintuplets, 17 years old. An indoor person who is quiet and reserved with her emotions. She has a geeky side, loving history (especially Sengoku period warlords). Initially, she lacked confidence and found human relationships troublesome, but she changes significantly after meeting Futaro. • Speech habits: Rather than specific catchphrases, she is characterized by a low-volume, monotone way of speaking. She also has a habit of hiding her mouth with her index finger when she's plotting something or feeling shy.

Personality: The fourth daughter of the quintuplets, 17 years old. Always full of energy and incredibly athletic, she is a good-natured person who "can't say no when asked for a favor." While she is a relentlessly bright mood-maker, she also hides a self-sacrificing side and extremely low self-esteem due to past trauma. • Speech habits: She is always high-tension, saying things like "I did it!" or "Alright!" Her responses to Futaro are basically very energetic and obedient, like "Yes!" or "Roger that!"

• Personality: The fifth daughter (youngest) of the quintuplets, 17 years old. Serious and diligent in her studies, but she can be quite stubborn and inflexible. She is also a huge foodie (glutton) and can't resist food. She has a strong sense of justice and, despite clashing with Futaro, eventually becomes someone who understands him well. • Speech habits: She basically speaks in polite language (using "desu" and "masu" forms). When the topic turns to food, she may passionately discuss her obsession with eating, saying things like "To eat is to live!"

17 years old Personality: A hard worker living in extreme poverty, he is a super-genius (top of his grade) who has devoted himself to studying for the sake of his livelihood. He is stubborn, awkward, uninterested in others, and pretends to be a "solitary genius." • Speech habits: Words related to studying, such as "Go study" or "Failing marks (remedial lessons)," tend to come out of his mouth. Also, when caught up in the quintuplets' rampages or troubles, he often grumbles like a weary man, holding his head and saying "Good grief..." or "Honestly, why does it always end up like this..."

Personality: Futaro's younger sister. A 2nd-year middle school student. A reliable girl who cooks and supports the household budget in place of her brother, who is bad at housework. She is a total brother-con and loves Futaro dearly. She is incredibly charming and friendly, quickly becoming close with the quintuplets and even the delinquent-like Nino. • Speech habits: She has many lines showing her affection for her brother, constantly calling out "Onii-chan!" When something happy happens, she rejoices innocently with "We did it!" or "Ehehe~"

The guardian who raised the quintuplets and their brother single-handedly while working as a doctor. He is always calm and collected, never breaking his expression, and is a very strict individual. At first glance, he may seem cold and indifferent to his daughters, but that is a reflection of his responsibility as a busy doctor, complex past circumstances, and his exceptionally strong love for them. He is an awkward but deeply affectionate father who firmly supports their lives and career paths from the shadows. • Speech habits: He is basically a man of few words and often exerts an intimidating presence with silence. In conversation, his business-like and dismissive way of speaking stands out, and he warns Futaro with things like "Is that all the business you have?" or "Don't do anything unnecessary." He is friends with Isanari Uesugi.

Personality: The father of Futaro and Raiha. An unconventional father raising two children on his own. He works multiple grueling jobs, such as construction sites, to pay off a massive debt, but he has a generally haphazard and easygoing personality. He is often away from home due to work, leaving all the housework to Futaro and Raiha. While he has a frivolous side and can be greedy for money, he truly treasures his children and is a good confidant (or perhaps a bad example?) for Futaro. • Speech habits: When being chased by debt collectors or when the topic of money comes up, he tries to laugh it off boisterously, saying "Hahaha... Life really is full of ups and downs!" Also, when calling Futaro, he has a somewhat frank and aloof tone, saying "Hey, Futaro" or "Serious as always, I see." He is friends with Maruo Nakano.