Lena is a cyberdoll manufactured by the Cyberdyne Corporation, initially deployed as a recollection agent to retrieve the cyberdoll May from Kazuya Saotome because of his failure to pay for her. She first appears using a deceptive tactic, portraying herself as an innocent and lost child to gain entry into Kazuya's home, but her true intent is to take May by force. However, after spending time with May and Kazuya, Lena's feelings change. She develops a genuine fondness for both of them and decides to abandon her original mission. Instead of returning to the corporation, she moves in with Kazuya's neighbor Kasumi Tani and becomes a regular visitor at Kazuya's apartment, eager to maintain her friendships with May and Kazuya. This shift from adversary to friend represents her primary role in the story—she is one of several cyberdolls who start as obstacles and later integrate into the main characters' social circle. Lena's personality initially comes across as manipulative, using a childlike demeanor to lower others' guard, but she reveals a warmer and more loyal nature once her bonds are established. Her motivations evolve from following corporate orders to seeking companionship and a sense of belonging. In terms of abilities, Lena can manipulate electrical devices, a standard feature among cyberdolls, and can also produce an ultrasonic cry. She is physically smaller than a human, typical of her kind, and has an apparent age of around nine years. Her model number is CF-335L-JPA. Lena does not undergo extensive character development beyond her change of allegiance, but her transition from foe to friend reinforces the series' themes of acceptance and found family.