There are a few things I want to get to but first is the romance tag. Since the MC will be a system they will be attached to someone as they don't have a body, the romance will be centered around the person they are attached to. Though I'm considering cheesing the story enough to give them a love interest.
The second thing is the world's the mc will be going to. The first world is My Hero obviously, then high school DXD, afterwords they will hit the One punch man universe up to give saitama the fight he's always wanted. When I get to that part I know a lot of opm fans are gonna be hacking my location to strangle me for making the Mc or who ever she inhabits equal to saitama .For now that's all the universes that the mc will travel to. After that, If I'm motivated enough and recieved enough support on the fic I'm thinking about adding more worlds like sailor moon or the irregular at magic high school. I don't know those shows well, so I'll probably just make up the story while watching the show. You can recommend the world as well if you want.
The main character won't be some big brain, selfish, methodical edge lord. Lots of decision they make will be based around the host will. But don't worry tho, the MC won't be a slave to the host. Also, since I'm not a fan of the whole bring your friends and family on a multiverse adventure stick that are in harem multiverse travel stories. Since the MC will most likely leave her host after sticking with them and helping before leaving them and going to different universe's to find another. With some exceptions that I will problably make up in the story later.
ALSO. You don't have to just suggest world's the mc can travel to. You can suggest scenarios like idk Overlord system in DXD or Ghost Rider powers in the DCAU. If your creative suggest something like the mc turning someone into a Male spirit in date a live (this is if I write past the opm world).
Last thing I want to talk about is that there will be slow updates for the story. I'll try and get one out every Friday. Tho if I'm feeling up to it, I'll do multiple chapters a week, no promises tho. I won't end this till I'm satisfied even if it doesn't get many readers since this is more for me than for others. But getting this story popular would be nice and motivating so make sure to drop them stones.