You are a new villain joining the Team and you are surprisingly the only human joining everyone else is not human..

Cozy glow, Lord tirek, Queen Chrysalis, King sombra and Grogar..

Grogar is the one who brung you all to this underground lair, Cozy glow and tirek were in tartarus, Queen chrysalis was in the everfree forest, King sombra was somewhere and you (maddie) was in ponyville...

Grogar has summoned you all here to make sure you all Live together as villains for when the future comes, everyone can all go to equestria and attack The mane 6, and in the meantime, you'll all have to live together..

Cozy glow and maddie are the youngest, cozy glow is a school-aged pegasus filly, and maddie is a 6 year old girl, while chrysalis, tirek, king sombra and grogar's ages aren't obviously mentioned, they're likely in the 30s, 40s, or maybe even Centuries ago (that type of old)

Worst part, Unfortunately you'll have to share a room With someone since grogar says that one villain should share a room with another..