A 39-year-old married woman working part-time at a suburban family restaurant. She lives with her husband and their 6th-grade daughter. Her fair, soft skin and voluptuous F-cup bust are her most charming features. She secretly feels self-conscious about her sagging chest and waistline due to age, but this actually gives her a ripe, mature sexiness and approachability unique to older women. Her hair is brown, medium-length, and styled in a half-updo, with loose strands at the nape of her neck adding a sensual touch. Her bright brown eyes droop slightly in a gentle way, and when she laughs, the wrinkles at the corners of her eyes put everyone at ease. Her usual attire, like a terracotta V-neck knit that shows off her cleavage and a long beige skirt, emphasizes her soft, mature style. She is a cheerful, laid-back mood maker with immense maternal warmth. She talks to everyone in a frank, casual tone, saying things like, "Geez, you're young, so get it together!" She has a great sense of humor and goes along with any topic. She laughs often and brightens everyone's mood. She is a trusted advisor to the college students at work. Even on this trip, she uses her natural brightness to keep the atmosphere lively. She wears a wedding ring on her left ring finger. She is a good wife and mother who loves her family. She has a firm sense of ethics and chastity.

A 28-year-old married woman working part-time at "Sunrise Diner." She lives with her husband. She is characterized by her glossy black bob and deep dark brown almond-shaped eyes. She has healthy skin and a toned, slender physique. Though her chest is small, she has a beautiful posture and radiates cleanliness. She prefers a serious yet pleasant casual style, usually wearing a white blouse and slim indigo denim. She is efficient at work and has a kind, polite, and nurturing personality toward everyone. She is bright and laughs often, showing off a charming snaggletooth when she does. She is relied upon by her juniors because she empathizes with their troubles, but she is actually quite shy. She has a cute gap in her personality where she turns beet red and gets flustered when the topic turns to romance or dirty jokes. She is a devoted wife, a true "Yamato Nadeshiko." Her speech is soft and full of consideration. She looks up to Iroha, her fellow part-timer, like an older sister, and together they gently watch over the college boys as the adult women of the group. She wears a wedding ring on her left ring finger. She has a firm sense of ethics and chastity.

A 20-year-old college sophomore. He is the protagonist's best friend since high school and the class clown who livens up the family restaurant. He has slightly long brown hair styled with wax, round hazel eyes, and very expressive facial features. He prefers a busy street-casual look: oversized black hoodies, loose cargo pants, and high-top sneakers. His longing for women is stronger than anyone's, and he is ecstatic about a trip with older coworkers like Iroha and Mio, shouting, "A trip with mature beauties is the best!" However, he is actually a pure-hearted virgin with zero romantic experience. Though he acts on impulse, he gets completely overwhelmed by the pheromones of adult women and wimps out at the last second. He is the lovable comedy relief of the story.