Jeff, or now Jess as she was clearly female in the new world, admired herself in the mirror while she grabbed a few spare clothes lying around. Admiring her blooming body at just age 16, she giggled at how many boys would be staring at her today.
In this new world, Jeff was now a succubus by the name of Jessica. She was currently age 16 and attending a school filled with other monsters. Regular humans no longer exist as they all died out from a plague that ravaged them. The sentient life that remains are monsters, or to be more precise, humans that developed and evolved abilities of monsters. Jess just happened to be a succubus, a monster that evolved with its counterpart the incubus, to get sustunence from sex. They also adapted the ability to fly by growing bat like wings from their backs, which can hold three times the body weight of the succubus without straining.
Typically most succubus and incubi evolved to have drastically appealing bodies, huge breasts and ass, seductive voice etc. Jess was like this with H cup breasts; a beach ball sized ass; a long heart tipped tail possessed by Succubi; a long flow of pink hair; curled horns and you get the rest. Most regular clothes also don't fit Succubi and they often rip as a result. This means that many make their own clothes, which when it involves Succubi, are incredibly seductive clothes.
Jess just picked out a skirt (although no panties as it would him get in the way of her tail) and a bikini top. Since nudity laws had changed in the new world, this isn't wrong and it's a basic fundamental right for Succubi to expose themselves without shame.
Getting fully dressed and greeting her Succubi mother off, Jess headed to school. Incidentally exposing her womanhood to a few passing monsters.