- Childhood Friends: With Shizuku.
- Even the Guys Want Him: Seiya is just as hot for him as any of the girls.
- Like Brother and Sister: With Shizuku. He even calls her "big sis".
- Not What I Signed on For: When Akiho agrees to be his girlfriend, he finds out some things about her which he has some trouble getting used to.
- Oblivious to Love: He is quite popular with the girls in his neighborhood, but remains unaware of, or is simply not interested in, their romantic inclinations towards him.
- Only Sane Man: Is always the first to call out the bizarre antics of his girlfriend, not to mention the rest of the harem.
- Unwanted Harem: He got a grand total of 7 girls and 1 guy interested in him.
- Class Representative: She's a model student and popular girl in her class.
- Emotionless Girl: She speaks in a very monotone voice.
- Lethal Chef: She tried to make Haruka a bento, it somehow became Kyubey.Bento: (to Haruka) Make a contract!
- No Social Skills: Hard to tell if it's this, or she just approaches sexual topics in a straightforward manner.
- Rei Ayanami Expy: She even looks a little bit like her.
- What Do You Mean, It's Not Didactic?: Her with intimate relationships.
- A-Cup Angst: She is jealous of the other girls' breasts, and in the wishing episode she wishes to get a B cup.
- Cannot Spit It Out: Although she makes several playful and obvious allusions towards him, she is too shy to take the initiative when things have a chance to get serious.
- Childhood Friend Romance: With Haruka.
- Feminine Women Can Cook: She's apparently a good cook.
- Like Brother and Sister: Haruka has her friend zoned pretty hard.
- Mrs. Robinson: Downplayed. She's a third-year while Haruka is a second-year.
- Ambiguously Bi: She previously attended an all-girl school and could only find romance with other girls, which is why she transferred to Haruka's school.
- Animal Lover: She owns two dogs, Butter and Margarine, whom she regards like human beings.
- Casting Gag: Wouldn't be the first high-class Ojou character that Amber Lee Connors has voiced.
- Growling Gut: Rina's stomach growls in episode 5.
- New Transfer Student: Transfers to Haruka's school in search of a boyfriend.
- Ojou: More of a western example.
- One-Gender School: She comes from an all girls school.
- Rapunzel Hair: Hair goes past her back.
- Animal-Eared Headband: Animal-Eared Hood more accurately. Cat ears.
- Animal Motif: A cat. She wears a god damn cat hood!
- BrotherSister Incest: Despite being Haruka's sister, she's just as interested in him as the other girls are.
- Entitled to Have You: She considers herself the only girl cute enough to be his girlfriend.
- Bishōnen: Times infinity.
- Curtains Match the Window: Red hair and eyes.
- Gay Option: Unbeknownst to Haruka, his harem also has a male option.
- Incompatible Orientation: He recieves a great amount of attention from girls in his school. Unfortunately for them, he doesn't swing that way.
- Narcissist: He enjoys the romantic attention of nearly every girl in school, despite not being into them.
- School Idol: He's probably one of the most popular kids at Haruka's school.