Offspring ( 子孫 / しそん / shison ) is the twenty-first chapter of the Elfen Lied manga series.
Bando is at first confused by hearing Nyu saying her name, then fully remembers hearing 'Nyu' from the assailant that maimed him, namely Nyu's other self, Lucy. Seizing and holding her by the throat, the blinded agent then feels past her hair ribbons for her horns. Casting her upon the ground, he realizes this may well be the enemy he wanted vengeance on so badly. She runs off, and his would-be pursuit is ended both by Isobe, and the confusion caused by several college students having conversations with 'Nyu'-sounding words as part of them. Flying into a rage, including threats against anyone and everyone present as he falls, Bando makes a spectacle of himself and is led off in frustration, his desire for revenge on Lucy even deeper and stronger.
A frightened Nyu finds Kouta and bear-hugs him, after which he anxiously gets them to class, once again thrown off by her displays of affection.
Entering the university research section, Bando questions why his treatment involves coming to such a small rural college. Isobe tells him that the scientists in question are top-notch and yet also almost the embodiment of 'mad' scientists, ruthless and perhaps unstable, often killing in the course of their experiments, even calling them for being beneath human standards of decency. They are the ones to help Bando if anyone can. Isobe warns they are in such an odd place for a reason, with the scientists also being 'accident-prone' and that he should watch his words around them. A man who introduces himself as Kakuzawa apologizes for the mess in his office area, then greets Bando and inquires as to his problems, even apologizing for his assistant's absence and the lack of tea to serve them. Kakuzawa shocks Isobe by cheerfully confirming an insulting remark against the scientists Isobe made in private with Bando.
Above them, Kouta, Yuka, and Nyu head for classes, with Yuka feeling a bit of anger at Kouta's denseness on certain subjects before joining them.
Doctor Kakuzawa carries on a conversation with himself, observing that Kurama is more merciful towards Bando than he has others in the past. Bando finally demands to know why he must undergo castration surgery, desiring to father children of his one day. Kakuzawa informs him of his infection, and that Bando has a choice: undergo sterilization or have his future children be horned Diclonius., taunting him with his hatred of such beings.
- This chapter introduces Professor Kakuzawa, the son of Diclonius Research Institute head Chief Kakuzawa.
- The cover features a contemplative, perhaps confused Yuka, her exact state of dress unclear.