It depends on how they got the new life, like if he died and was born into a new body, its reincarnation, but if he died and entered a body, its a transmigration
oh, also, I think an attached soul is more like a footprint, or like the memories, kinda? to like show that they've more lives
As you had said.
Reincarnation was the path for those who has died or for those whose soul has entered the samsara/ circle of reincarnation.
Therefore, the soul obtained a new life through the proper channel or natural law, thus be reborn as fresh lifelings. Regarding their memories, normally it would be wiped out tho. As for karma... who knows.
Next, Transmigration.
I believe that there are 2 kinds of transmigration.
The first type was the complete/full migration. The moving was targetted on the whole existence -body and soul. Well, we usually coin it as being isekai-ed, summoned, or transported.
The second type was the partial -only the soul was moved. Somehow suddenly, the person awoke in the body of someone else's, be it due to swapping, stuffing, or other cause.
and the terms of attached soul, terminologically, was more in line with the latter type. That's what I think, however his experience insinuating otherwise.
that's a new term...
but doesn't this mean that he was closer to a transmigrator than a reincarnator?
ah, but saying transmigrator wasn't quite it either....