Season
- Season 1 2006-10-04
Episode
- Episode 1: A New Life
- Episode 2: The True Form Homunculus
- Episode 3: You've Become A Little Stronger
- Episode 4: Another New Life
- Episode 5: To Protect Someone
- Episode 6: The Butterfly of Black Death
- Episode 7: Whether or not You're a Hypocrite
- Episode 8: A Night in the Dorm
- Episode 9: The Hayasaka Twins
- Episode 10: It Seems We're Well Matched
- Episode 11: Till Death Do Us Part
- Episode 12: Carnival
- Episode 13: Signs Of Death
- Episode 14: Who Are You?
- Episode 15: An Intermediate Existence
- Episode 16: New Strength
- Episode 17: When Dawn Comes
- Episode 18: The Escape
- Episode 19: As Long As I Can Protect You
- Episode 20: With Strength And Spirit
- Episode 21: Gone Into Flame
- Episode 22: A Decision Is Required
- Episode 23: Boy Meets Battle Girl
- Episode 24: When You Die, I'll Die With You
- Episode 25: No One Could Ever Take His Place
- Episode 26: Period
Buso Renkin Season 1 A Decision Is Required
The story begins when high school student Kazuki Muto is killed one night saving a mysterious girl from a monster, only to wake up in his school dorm, believing it to have been a dream; however, he soon finds out that dream wasn't a dream at all when a giant serpentine monster attacks him and his sister. Tokiko Tsumura, the girl he saved, explains that the monster is a homunculus. Kazuki had been attacked and killed by it when he was rescuing her; however, she, feeling responsible for him, revived him by placing a Kakugane medallion in his chest, serving as a replacement heart.
