It was just a speculation. I didn't read the novel or anything. But from several chapters back, we clearly read that Na In was ushered to a smokey room and when he got out, he lost some of his recent memories.
I really love it when they draw Kayden with pink colored flubbs. Wanna squish it and put my face on it and kiss it and I'll probably get zapped as heck but what a way to go (▰˘◡˘▰)
I blinked and the chapter was over