What Day

What Day (ナンノヒ "Nanohi") is the eighty seventh chapter of the Nisekoi manga series written and illustrated by Naoshi Komi, published weekly in the magazine Weekly Shōnen Jump.

Summary
At Chitoge's house, Chitoge sees members of the Bee Hive Gang hauling around huge packages. They tell her it's nothing, but are terrible at hiding that they are preparing for her birthday party. Chitoge reminisces about the crazy events that happened at her last birthday, and what she learned about what happened ten years ago. Chitoge wonders if Raku will come to her birthday this year as well.

Later in school, Raku is pleased to have recovered his locket from Haru. Chitoge asks if Raku remembers what is happening on Sunday (her birthday), and although he can recall many previous events, he doesn't remember her birthday. Chitoge hits Raku and leaves.

As Chitoge walks away, Raku remembers that her birthday is that Sunday, and plans to apologize to her later. After walking away Chitoge scolds herself for being so mean to Raku, although she feels disappointed that he doesn't pay attention to her. Chitoge returns to class, but finds it difficult to apologize, and Raku feels it isn't the right time to apologize as well.

By the end of the day, Chitoge and Raku have both not apologized, as they haven't "found the right moment" to apologize. As Chitoge broods about Raku, a baseball comes flying from the practice fields, and Raku pushes Chitoge out of the way. However, the baseball hits Raku directly in the head and he passes out.

When Raku awakens, he can not remember his friends, his school, or who he is.

Trivia

 * This chapter contains a character correlation graph, created by Mimiko, to help explain the relationship between characters.
 * Chitoge still has the stuffed gorilla that Raku bought her for her birthday the previous year.
 * When Raku is trying to remember what happened the year before, he references several chapters in the manga, including the forest trip, Tsugumi getting a love letter, and Marika transferring in.