
I want to know what is the reaction of the Duke or what will he do when he knew her daughter committed suicide by using the weapon he gave her (in the past timeline). I want to see if he will hurt the obsessive boyfriend or something

Oh hun your wish has been granted, when he heard his daughter commited suicide from the magical sword he gave for protection,he went crazy n killed EVERYONE, the emperor tried to control him again with his magical ring but since the Duke had lost his mind, it didn't work out-- Oolala, That so-called stupid emperor died

Here's more if you want a really detailed spoiler
http://www.mangago.zone/home/mangatopic/10791226/
I swear after you read this, you'll love the father even more.
I do not know what to feel knowing what will happen next