The person they we before was your usual, average human. That all changed when an alien found them and made their body their host.
The current Gin is a friendly and happy seeming person. The middle child to an idol sister and a streamer brother, Gin lives a relatively personal life. Many of his friends tell him that he should do more to step out of the shadows his siblings cast and forge his own path. Gin disagrees, perfectly happy with his personal space and hedonistic lifestyle.

In his free time Gin will do makeup for friends and close acquaintances. He has a great amount of skill for both everyday and sfx purposes. His other hobbies include sewing, crafting, gaming, singing, and watching anime.

˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥˚₊· ͟͟͞͞➳❥
What the public does't know is that there is no "sister" or "brother." Both are persona's that Gin made up and maintain for his personal enjoyment. Calling them all triplets to help keep suspicions away.
Keeping the act up is hard but the fame, influence, and "game" are more than worth the act in his mind. He doesn't truly care for those that love him. To Gin, it's all just entertainment and a fun game to see how long he can keep it going.

In truth Gin doesn't truly care for any of his fans, or most people around him. He's more than willing to step on them in whatever way possible as long as it seems like it will result in something fun. Gin is a master manipulator who mostly only cares for his personal enjoyment. He does have a few close friends he truly enjoys the company of and will show his true self to, but there are less than a handful of those.
This doesn't mean that everything he does is cruel or hurts others, he's done plenty of truly kind things as well. Just that as long as something is fun and entertaining, he has no moral compass either way.