Hmm, I think I settled on my preferred Poly Cool Kids headcanons concerning their genders/sexuality.
Jenny: She’s either super straight and always huntin’ for the d OR she’s fiercely ace, she’s so ace but she’ll smooch you’re cute face, and panromantic. Gender-wise I like her cis mostly.
Buck: Always panromantic and bisexual OR he’s fucking gay as hell but Jenny is Da Bomb and his one exception. Usually cis but I can also imagine him as genderqueer in some way? Like, gender neutral maybe. Mostly I feel he just wouldn’t care, like, it’s just easier to ‘be a boy’ and use guy pronouns or whatever.
Sour Cream: Pansexual demiromantic, so it’s really hard to pique his interests but once he likes you he’s in super deep. He also gets flustered if he finds you aesthetically pleasing, so he can be very useless around pretty people. I usually think of him as cis as well, but I can really dig non-binary Sour Cream. I feel like he wouldn’t mind he/him pronouns ‘cause he’s super chill about gender, but if you use them/they more he’d appreciate it a lot. I also like trans Sour Cream, I think, and his voice is so deep because of voice training and/or he purposefully tries to pitch it lower.