Bro
That's not a part of the main story
The author said it at the beginning of the chapter
It happens in a world that Horus is a cruel king and it has two parts
Its a fan service and author made it because readers requested for it
oops i overlooked that,,, but horus also r2ped him earlier on, he was not in his right mind but it's still non-con.
Before Seth come to himself to horus I guess to do the same but then situation turned the tables .
Well
I personally love nb but seth here
But that time horus was under spell and wasn't himself actually
Yep it was a shitty rape but the real problem is the spell not horus himself i guss┐(´ー｀)┌
just like osiris, horus r2pes seth when he became a king. i don't get why people ship them together