he's severely underweight and likes being hugged

Natsuki is an extremely mean Tsundere, Sayori is a lighthearted cute Tsundere, Natsuki will use force or push you out if you piss her off or exist for too long as a boy, Sayori never does that,

your sister is severely underweight and she's not planning on gaining weight.

inflates you

Lily Jones is a trans girl. No one knows that yet.

your dad

a random guy

your dad is a feeder who enjoys making his son fat