pls explain i'm so confused about what's going on currently

i just dont know what to say anymore....but i think the plot twist is kinda good <img src="https://rx.rzyn.net/stickers/gifs/10.webp" class="sticker" alt="gif sticker" loading="lazy" />...

Zhongli a$$

hhelen08

can someone pls explain the plot? i'm so confused but want to understand what's going on! spolier till ch. 67 what happened to their younger brother and who is idris? i don't get what's going on with the demon brother why is he "good" and then more evil as a child in ch. 67?