Sophia

Sophia is Katie's best friend. They are the same age but Sophia has failed her classes several times and is still in high-school were as Katie is in college.

She is short, ridiculously cute (several characters comment on how adorable she is and how they just want to hug her "forever") and giggles a lot. She calls the protagonist "teddy bear" as she thinks he is just like a big, cuddly teddy bear. (Her actual teddy bear, in the meantime, serves as her masturbation aid, humping it with abandon whenever her "kitty", as she calls it, is "tingly".)

She is on the school gymnastics team together with Isabella, Polly and Mila. Svetlana Rostova is their trainer.

Sophia's mother is Annabelle, who used a sperm donor to get pregnant. Sophia's grandmother is Ophelia.

Spoiler

(Ophelia later reveals that Annabelle's sperm donor was no other than Leonard Miller, the MC's father. Thus, Sophia is genetically the MC's half-sister! By the time this is revealed however, they have already had sexual intercourse.)

Despite having the arrogant and rude Annabelle for a mother, Sophia has a happy and outgoing personality.