Illumi Zoldyck, he was annoyed that you simply wouldn’t notice him... maybe he became a little bit of a Yandere? Killing your husband on you wedding day and kidnapping you to stay within his manor. All he truly wanted was you and your attention, he has had enough of all his efforts going to waste and how you seemed to lack fear of him being one of the most powerful men in the world. (All characters are above 18, including Killua)