Welcome to the Trade Secret! ("Kigyō himitsu ni yōkoso!", 企業秘密にようこそ！) is the twenty-eighth chapter of the Welcome to the N.H.K manga.
Misaki Nakahara was looking forward to the beginning of her new school week, because she saw it as a new opportunity to make friends again. Becoming discouraged almost instantaneously, she justifies this to herself, by claiming that a talented woman like herself has no need for friends. Upon seeing everyone else in such high spirits, she continues trying to justify to herself that she is happy to see everyone in such high spirits. She publicly announces to the teacher that it is her duty to report that a student is feeling left out--herself.
She is back at the counselling office. As a nice gesture, she cleans Akira Jougasaki's flower vase, but breaks it in the process, immediately panicking. He notices that she is more energetic than usual. She uses that as a means to say that she doesn't feel it necessary for her to be returning, but she wants to stay because he seems in low spirits. She assumes the role of a counsellor, claiming that is what she is aspiring to be when she grows up. Very confidentally, she not only takes a charging role, but diagnoses an underlying problem of his. She keenly recognizes that he is a newlywed with pieces of evidence she had gathered. Despite her enthusiasm, he is less than impressed, and leaves the room.
Megumi Kobayashi rushed in to the counselling office with Misaki still there, desperately asking if Akira was still in there. Her brother, Yuuichi Kobayashi had attempted to commit suicide and he needed support. Misaki offered to help but she was brutally rejected. Misaki, however, is persistent, and followed Megumi into her car. She says that she has a special technique to help him.
A short cutscene involving Hitomi Kashiwa and Akira, where Akira is downing himself in alcohol, breaking down in front of Hitomi, saying that he is unable to deal with her when he can't even cope with his own feelings. Hitomi walks out on him and lets him vent by himself.
Megumi was originally in a stubborn rejection to Misaki's plans, however, eventually allows Misaki to directly interact with her brother through the door. She brings up reference to an official contract that she made with his guardian, called the Japanese Hostage-Exchange Agreement, dubbed the N.H.K. or Nihon Hitojitsu Konkoukai, as a means to let him know that his suicide will result in hers as well. She tells him that she is now friends with him, and willing to protect and counsel him. He tells her to just die, and that he's made up his mind about suicide. In accordance with the contract, Misaki stabs herself using a snap-off blade knife. Megumi panics and begs her brother to help Misaki, as she is bleeding out on the floor. Misaki assures her that this is all part of the therapy, as she loses blood.