Ren is the oldest child of the Maaka family and the only boy. He has long since went though his stage of maturaty though his mind is somewhat childish still. Hes a master playboy with the ladies and will do anything including going into a sexual hotel to drink there stress. Though he is very hard on his middle sister, Karin, he does it out of love more then out of just being a jerk.
[Edit]Ren Maaka (真紅 煉 Maaka Ren), the oldest of the Marker children, has no qualms about sucking blood, and believes vampires to be superior to humans. However, he prefers female victims, seducing women and often spending days in their company before he's done with them, and refuses to suck on male blood. Ren sees the act of biting as a metaphor for sexual intercourse, and often commits both acts simultaneously.
Ren often appears annoyed at Karin for her seeming lack of vampire abilities and her friendliness towards humans. While he will listen to his father Henry, Anju is often the one who will calm him when he's annoyed or subtly prod him into acting in certain ways. He greatly fears Elda Marker, whose overly affectionate manner when he was a child causes him to flee at the mere sight of her. Despite his seeming to always harass Karin, he does love her and after her capture, aids in her rescue. When he finds her, he tells Bridget Brownlick that he is the only one allowed to bully her. While Karin escapes with Kenta, Ren controls Bridget by having sex with her. She becomes pregnant with the first vampire child to be born since Anju. At the end of the series, he tells Karin he always loves her before finishing the process of erasing her memories relating to vampires and the Markers family. In the anime television series, Ren Maaka is voiced by Junichi Suwabe in Japanese and Jerry Szombathy in English.