I sekai tensei otherworldly reincarnation

Satorou Tamura is summoned into another world as a hero...a~nd then loses the status of hero because he's given a seal that seals away his magic. But wait, that's not all! The seal was made as a weapon by a council of wizards for the church at war with monsters ruling a dungeon whilst simultaneously at war with a cult of witches. But wait, that's still not all! The original vessel of the seal chosen by the church actually refused the seal but inherited the hero's power form Satorou as he lost it BECAUSE of the seal. But wait! Did I mention he refused the seal out of fear for losing his nobleborn magic because his dad was actually a former member of the wizard council that actually made the seal but got kicked out and replaced by someone stronger than him so now his dad basically crashes out at the slightest sign of weakness? But wait - I didn't mention that the entire first volume is a prologue in which the main character will die at the end and be reincarnated into that very same world as the son of a man that's the cousin of the strongest membernof that very same wizard council whom also trained the dude who inherited the hero's power.

sounds interesting yet...come read it