|The below list is by no means exhaustive, so if you're interested in something not listed here, by all means ask! Age-wise, I play Sonia anywhere between her early 20s and mid 40s, so any point in there is good with me.|
Sonia is pansexual and too Betan to give a shit about someone's genital configuration; as far as she's concerned, as long as everyone's having a good time, she's happy. She's an unapologetic flirt, even when she's only teasing, although more often than not, her overtures are genuine. (This tones down a little as she gets older.) Sonia spends the entirety of her adolescence and young adulthood in war, and due to her status as an Imperial Princess, getting laid without someone getting in trouble is damn near impossible, which has historically led to sneaking around, pretending to be a local. This is significantly less of a problem after the death of her husband, once she's moved on: when she wants something, she'll go out and get it herself. Sonia has always been a sexually and romantically assertive person as well as enthusiastic. She knows what she likes, and what she likes, she likes a lot.
Depending on the canon point (and the other person), Sonia prefers no-strings-attached sex or friends-with-benefits arrangements. Sexual friendships are something she's quite comfortable with, but emotional intimacy has intimidated her for most of her life. As a young woman, she shied away from it fiercely, unwilling to give herself one more loved one to lose in the war. After her widowing, she is far less skittish about it, and might not even turn it aside entirely, but she has no interest in remarrying.
Bolded items are IC kinks for Sonia; unbolded are kinks that I enjoy subjecting my characters to OOCly, because I am a bad person.
(code courtesy of dragonpunch)