Not to mention the multiple traumas mental and physical that will scar him for life; especially in this arc, his actions were in reaction to the traumas she has caused him.
That aside, looks like we have some explanation: Dad's skill is back! Now, to figure out how and why. Is it timed? Is it because something happened to the Skill Taker? Is it because he met the requirement that Skill Taking gave him for cancelling it? Too many questions, not enough answers.