This is just bad. The beast girl child is trying to kill herself, constantly making assumptions, and has almost zero trust in the main character. I'd understand her behavior if she were still being manipulated, but it seems like she's not. Maybe it's the time skip that she has those thoughts?
I can't believe I now find both her and the Water Goddess annoying, compared to the earlier chapters when they were still at the orphanage and everything they did was cute and funny. But now, they're suddenly getting on my nerves.
I hope the MC gives that God of Death a brutal beating; she started all this.