And so, enter Yoshie! Part of that strange generation that is so dead set on seducing humans for their magic!
From a very young age, Yoshie was taught the story of how magic dried up. In the retellings of her time, humans are depicted as selfish creatures that stole all of the world's magic for themselves. Demons like Yoshie were forced underground in order to hide from human technology. Once, they were a proud race with huge wings and an appetite for luxurious foods. Now, demons have devolved their wings to conserve magic (and space,) which becoming rock eaters. Don't ask about the sciences, but Yoshie can straight-up eat rocks to get minerals.
From an early age, Yoshie was on her own. Demons very rarely stay with their birth families, as there is very little space in the assigned housing. Instead, young demons are assigned to whoever has space until they turn ten years old. At that point, groups of ten year old demons move into the next open house. As they grow older and bigger, they are sent to live with the next "family" which has an open space for someone their size. Because of this, family isn't really a term that demons use. Yoshie doesn't think of her mother and father, or her housemates, but instead thinks of the house itself. She has been constantly moving since she was born and never had a chance to settle into a community, but that's fine. Demons are just gears in a clock and moved to wherever they fit.
To a young Yoshie, the underground Kingdom of demons was all she knew. Which isn't to say that it's a horrible place to live. Her home sparkles with colourful gemstones, and is vibrantly painted: Sunlight doesn't reach this place, so colours never fade. There is no sky, but the gems on the ceilings sparkle like stars. Demons don't have a proper substitute for the sun, so their skin is deathly pale and they can't grow many plants for food. Their diets are almost entirely meat and rocks.
This is all important, because it's what led to Yoshie deciding she wanted to seduce men. One day, Yoshie was graced with a luxurious basket of fruit. Only once in her life has she ever eaten fruit, but it was something she would never forget. After that, Yoshie decided that she wanted to go to the surface and learn how to bring more fruit to demons. Yup. That's her Little Mermaid story.
To achieve this, a young Yoshie had to attend a specific academy for teaching little demon girls to steal hearts. The students there learned human culture (often through outdated means,) and were essentially taught to be housewives. From there, every girl had to quickly form her own strategy. Space was still an issue to demons, so while the school was important it was also low capacity. Yoshie was boarded there for a little over a year before she was assigned a human target and flung onto the surface.
Where she failed to steal hearts. Repetitively. It wasn't only hard to get close to humans, but hard to survive on the surface. The Demon Kingdom was tiny, but it provided for its people. Yoshie had no idea how to *CURRENCY,* or how to learn more about fruit. She also didn't understand love in any form, other than physical.
The "official" process of stealing hearts was a harem anime: The various kingdoms would send one or more candidates to a human with a lot of magic. The idea was to better their chances of winning love by sending a variety of options. These harem scenarios played out until the human picked one lover, gave away their magic, and was then was often dumped. Yoshie was sent into numerous harem scenarios where she failed to the chosen candidate, over and over. It was exhausting.
Her story starts with her most recent harem. Yoshie was been sent to compete against an angel girl named Charlyt... in a losing battle. Not because Charlyt is particularly good at her job, either! But because they were assigned to an asexual-aromantic girl named Felicity. Aaand there's rrreally no winning this one.
