|Behind the Scenes|
|Debut||A World Replete with Death Throes|
Friender (フレンダー, Furendā) is a robotic canine and undying companion to Casshern. He originally belonged to a girl named Root until she succumbed to the Ruin. Originally Friender blamed Casshern for this but they made amends as Friender forgave him. He currently lays in wait with Ringo for Casshern's return.
Friender is a robotic canine with all four limbs, bright yellow eyes a long tail and no signs of Ruin. He is mostly black plated but on each leg their is a gray patch where the limb connects to Friender's torso. Friender's mouth is also a tan color and his ears are white and red, resembling Casshern's battle helmet ears.
Although Friender is technically wild life and a lower intelligence, he displays his own unique traits. Friender is known for being quite intelligent as he was able to gather Jin and his group in order to hunt down Casshern. Friender is also very bold as he will attack anybody to protect someone he cares about, and the most notable trait of Friender is his undying loyalty towards his master.
Casshern SinsFriender's past is completely unknown, but he was found by a young girl named Wrench. Wrench to Friender into a community of Robots waiting to Ruin, where Friender showed no signs of it himself. Wrench began to worry that Friender wouldn't fit in and she would die before him. Not long after a man named Casshern arrived and the community tried to devour him as a way to live, Wrench died along with everyone else who Casshern attacked to defend himself, Friender witnessed this tragedy and held a grudge against the for murdering his master.
Friender hunted down and found Casshern along with a man named Akoz. Casshern gave himself up to Friender, allowing him to take revenge. Instead Friender forgave Casshern and decided to travel with him. Friender accompanied Casshern on his journey to reveal his own past, but Friender was only interested in gaining a new master. Friender would protect Casshern from others as they could fight together and he would attack Casshern to keep him in line from hurting others. While battling a group of Bandits, Casshern helped Friender to escape a falling platform which crashed atop Casshern and trapped him underneath. Friender, being the loyal companion he is went on to seek help. It was not long before he found a group of friendly robots and humans that took him in thanks to their leader; Jin. Friender and Jin instantly had a connection due to their understanding of each other, Jin also not being able to Ruin or decay. But keeping loyal to his master, Friender leads the group to free Casshern, which they suceed in. 
Once again Casshern is backed into a community of people who wish to devour him but Friender stops the massacre this time, holding Casshern back while Jin consoles his people not to murder Casshern. Jin and Friender part ways as they say goodbye to each other. Friender and Casshern continue on their journey where Friender stays loyally by Casshern's side until Casshern leaves one final time to confront Luna in order to stop her tyranny. Friender would then wait simply by Ringo's side until Casshern would return. 
- 02. A World Replete with Death Throes
- 03. To the Ends of Agony
- 05. The Man who Killed the Sun Named Moon
- 06. Reunited with Fate
- 11. By One's Calling
- 12. Turn the Time Lived to Color
- 13. The Past Rises Before My Eyes
- 15. The God of Death Dune
- 17. The Glass Cradle
- 24. To the Wondering, Blooming Flowers
- Friender was the inspiration for Rush from the video game series Mega Man. In the 1970s anime, Neo-Human Casshern, he had the ability to breathe fire and transform into different vehicles for Casshern to use. In Sins, he is just an ordinary robot dog.
- Interestingly, despite being near each other for the majority of the series, Friender and Lyuze have no interaction between each other, even though they go into battle together.