AND THE CHEEKS WERE CLAPPED!!!!
Yay!
Now onto my conjecture.
And no I haven't read the WB/Novel so this is based on the manga only
Anyways back to the whole thing with the Guru & Sage
I bet the demon they killed was their legit son and that son was probably engaged with the pope which is why she's complaining and asking to be called shin's mom cuz if guru & sage's son hadn't died and shin was adopted like same events happening he would've technically became the pope's Step son
But because the son died there was no wedding and thus the Guru & Sage ended up "divorcing" due to probably differences in how to move on but then shin was found and they've slowly mended their relationship
But that's just my idea