Anybody confused: you need to read in the following order ->
1) The Most Heretical Last Boss Queen: From Villainess to Savior (18 chapters)
2)Higeki no Genkyou to Naru Saikyou Gedou Last Boss Joou wa Tami no Tame ni Tsukushimasu. - To the Savior (13 chapters)
3)Higeki no Genkyou to Naru Saikyou...