The Third Brother [Slow Update]

One For All and All For One. One of the strongest quirk known to mankind. A quirk the once belong to two brothers. The quirk that allow the user to steal other people's quirk and the quirk that can be passed for to the next generation.

But what if there is actually a third quirk? A quirk that belongs to their youngest brother. Their brother who had died years ago.

And what if instead of a quirk that can be passed to others, the quirk can passed down the soul to others?