Thread:Blue Luna/@comment-26056057-20150718112149/@comment-10733658-20150718112506

I can answer that question very easily -- the anime completely abandoned the arc that addressed all of that. The closest the anime got was the Twins, but their presence is never explained.

There's an entire arc in the manga, which deals with Kaneki tracking down Dr. Kanou. He finds out that Rize was still alive, but held prisoner as part of Dr. Kanou's experiments -- that is where the Twins come in. At the end of the arc, Yomo rescues Rize and was keeping her at his home.