01. Does your character believe in true love or soul mates? Love at first sight? Hahahahaha. Hahaha. That's silly and you should feel silly. No. Of course not. That's nonsense.
02. Are they or have they ever been in love? Never ever. She's been pretty isolated, and she doesn't think too much about it.
03. What are their general feelings about sex? Indifference? Awkwardness? She thinks it's strange that people feel the need to get naked and mash their genitals together. The idea of it doesn't necessarily seem all that fun to her, and she kind of laughs about it. She thinks it makes idiots out of people, thinks that people do all kinds of stupid things for sex.
04. How do they feel about sex without love? Indifference and awkwardness. Does love make a difference?
05. What about sex before marriage? Indifference.
06. What counts as cheating and is cheating forgivable? These are honestly questions she's never considered. I think that if she was in a relationship with someone and they cheated on her, her response would probably be to inflict some serious pain, though.
07. Have they or would they ever cheat? Nope, and ... I don't know? Yoona's actually rather self-centered, so it wouldn't surprise me if she cheated on a partner because she didn't think of the other person's feelings.
08. Are they a virgin? She is such a virgin.
09. First partner? Most recent? See "such a virgin."
10. What sort of experience do they have with sex? See "such a virgin." And honestly, the answer is none. Masturbation doesn't particularly interest her, either. She doesn't really get sexual urges, and when she does, she tends to... build something that blows up. Really. Processing her sexual feelings is complicated, because of inexperience and lack of information, and she has somewhat limited physical sensations — so she just ignores it. It doesn't make her unhappy, really.
11. How comfortable are they with their body? She's fine, but ... she doesn't want you to see her naked.
12. With their partner's body? See "such a virgin."
13. Who gave them "The Talk"? She's never had The Talk. She's done some reading and watched some movies and TV. That's about the extent of it, and if she had questions she asked her uncle, but the conversations were brief.
14. Post-sex habits? Weird habits? See "such a virgin."