@dokidoki
Correct me if I'm wrong, but because Devil papa inserted devil energy into His, she gained demon energy and could sense it, and I think she's part demon now
(Also the fact that her body could accept that different energy means His is special (?) )
But I assumed that she had that "power" before anything happened, as she was really good at noticing other demons before that (I think)
Also the earrings I think they talked about if one of them was hurt, the earrings would make it that the other would be hurt too (or was it die)
oh found the chapter: https://mangadex.org/chapter/481942/3