This is a story about bravery, love, and humor.
Jaune Arc, the fourth oldest of the Arc family siblings, after a mission to kill large numbers of Grimm kills his parents, he and his seven sisters Bianca, Olivia, Rosemary(Rose), Karen, Aqua, Violet, and Jade(all in order from oldest to youngest with Rose being Jaune's fraternal twin), now live by themselves in the house and with the money and family heirlooms left for them by their parents. Bianca and Olivia work as huntresses and Rose, Karen, Aqua, Violet, and Jade are in huntress school(the author picks the school, but if it is signal Rose has to take Jaune's spot on team JNPR, it would be ANVL, Arc, Nikos, Valkyrie, Lie, same partners), while Jaune is not allowed to be a hunter because his sisters care too much for his safety. One day while his sisters were out for a mission and school(Mr and Mrs Arc died when Jade was 4, Violet was 5, Aqua was 6, Karen was 7, Jaune and Rose were 8, Olivia was 15, and Bianca was 17) a 15 year old Jaune wonders away from the house with Crocea Mors(sword) and Crocea Luna(shield).
Even though he has been secretly training in using a sword and shield for four years, it wasn't enough to help him in defeating 5 Beowolves and 3 boarbatusks. Before he gets killed he unlocks his semblance, The Overlord, which randomly unlocks in different people. He survives and gets compelled to go to the tower, which holds knowledge, weapons/armor, and artifacts of past Overlords (the author has the choice on what those things are in detail). He sees that the towers heart has added aura and dust to itself to adapt to the new world and created an orb that changes to fit the new Overlord's preferrence(the author picks what the orb turns into).
The author can choose if there are any minion hives left, how many in total, and what they are besides the recommended brown, red, green, and blue, as well as gnarl and the other more importantly named minions. The author can take the story from this point, weather gnarl(he is the one who greets Jaune in the towers and shows him around), gives him a mission to find past Overlord stuff or train. A harem could be good for a overlord(I did say that his sisters really care for him, if you add them it's your choice), you pick who and how many join it. But the orb unlocks his aura and magic, no choice since it is connected to the tower heart and he already has his semblance.
Have fun writing this idea, PM me if you want it, only one can get it. Review for feedback. Also the first one who accepts this challenge will have their name on it before I take it down a week later.
Update: If you read the the title and the summary you can tell that I got ride of the ideas for adding the other three worlds to this challenge. This is now an Overlord X RWBY challenge with the option to add more worlds if they want.
Flamers will be ignored as well as impolite guests, at least have the courage to tell me you hate it with your own fanfic name.