I'm confused myself tbh but i just wanna post this comment
Invisoap = invisible soap
1. "Doesn't exist in this world" is mentioned several times in this chapter and it is stated that the invisoap is possible to exist somewhere else, perhaps alternative universe. The fact that the invisoap is invisible but still cut through the gas thingie, we can assume it is exist and not exist (at this universe) at the same time. The only way to know whether it's exist or not is for it to cut something, if not, we can't say for sure it is exist or not. Boom, The invisoap bubble paradox, soapdingër.
2. The bubbles came from the joestar birthmark, so perhaps it has some connections to josuke 8's predecessor, that is Johnny joestar.
3. If you look closely to the zoomed in soap bubble, it doesn't seem like it is spinning in one axis. So how many axis? Perhaps it's infinite amount of axis it is rotating/spinning in (point 2).
4. Regular soap bubble only take a "thing", but the invisoap act's like okuyasu's the hand's attack. The invisoap take a "thing" whether it's small (wonder of u hat) or big (mamezuku donut hole) and then the "thing" taken by invisoap is gone.
Bonus: cmiiw in this one part, but where's okuyasu? I think he became one with josuke 4 in this world (but not because rokaka fruit).
So here is my conclusion:
There are infinite amount of alternative worlds where josuke 8 fight josefumi (doctor). When josuke fired his regular soap bubble, the soap bubble form together with the bubbles from the other alternative worlds. you have seen it right? A bubble form together? Yeah, just like that. Thus where it's originally spins in one axis, it now spins in infinite axis. When native soap bubble pops up, it release the accumulated and formed together foreigner soap bubble, the invisoap. The native soap take/steal a "thing", but it's not gone. The "thing" taken by native soap still exist in this world because the native soap does exist in this world. But, the invisoap acts different because it itself is an outer worlder. When the invisoap takes a “thing” the taken “thing” become not exist anymore because the invisoap which contains it doesn't exist in the first place. So to naked eye it just gone, like how [the hand] works. It sent the "thing" to gods-know-where alternative universe. At the few last panel, josuke tries to fully control it (the bubble became unstable (?) thingie) then shoot it. If my theory is true, then when josuke shoot it and the native soap pops up, the invisoap is released and at a controlled-before trajectory. So if the aim is accurate, wonder of u is done for.