The Disappearance of Nagato Yuki-chan, Vol. 4

"When Yuki is grazed by a car on her way home from school, her minor injuries belie the drastic change that has taken place within her: the 'Yuki Nagato' after the accident is not the same person as the Yuki from before. The new Yuki has all of the same memories, but they feel as if they were lived by someone else. How will Yuki's fellow club members react to their new friend? And how will Yuki respond to the lingering impressions of her feelings for Kyon?" -- from publisher's web site.