Is she dead for real?
Please spoil me some info..:(
dont know. Judging by in-game random dialogue, Bronya thinks that Seele will one day return to her.
This is what I found
However, the experiment failed and Seele’s body decomposed to quantum level. In order to succeed Seele’s will, who became her substitute, Bronya actively volunteered for the next experiment while preparing for its failure. In the experiment, Bronya was faded into complex number matrix dimension, where she had a fateful encounter with Seele, which was Bronya’s real intention all along: to meet and stay together with Seele forever. Seele accepted Bronya ‘s feeling but still convinced Bronya to live on. Thus, making the experiment successful.