Wald is introduced as a muscular, impetuous martial artist, fierceful in both appearance and personality.
It is unknown where Wald was born. He was raised by only his alcohol addicted father. After his father's death, he moved to Downtown. He felt really lonely, however, and therefore established the Saber Vipers, which he referred to as his "holy place". He resorted to raw power ever since.
The rivalry with Wazy Hemisphere, leader of the youth gang Testaments, appears to define his existence, a trait admired by his fellow gang members. Upon their first visit to Downtown, Wald makes sure to intimate Lloyd Bannings and the rest of the Special Support Section. However, during Zero no Kiseki, Finale: "Crossbell's Longest Day", he fights off the brainwashed Guardian Force members together with Wazy so the SSS can make their way to the Sun Fort.
The life Wald has gotten used to drastically changes at the beginning of Ao no Kiseki, when Wazy joins the SSS as a temporary associate member, leaving his rivalry with Wald behind him. Wald challenges Wazy to a last duel. Wald loses and realises that Wazy had been holding back all this time. He falls into a depression and utterly humiliated, he spends his days indulging in drinking.
He is then scouted by Mariabell Crois. She provides him with blue Gnosis as her test object. As Gnosis enables the "spirit to stimulate physical change" and Wald hungers for power like no other, Mariabell concludes that he has great compatibility with the drug and that he can Demonise without losing control.
During the Assault on Crossbell City, he destroys Downtown in his demon form. He even tries to follow up Mariabell's advice to destroy the other Saber Vipers in order to gain more power, but is stopped in his tracks by Abbas and Ashley.
Still anxious over his relation to Wazy, Wald comes to the realisation that it had been his best friend, not his sworn enemy, all along. He battles the SSS again in the Azure Tree, but Wald is overwhelmed by their immense growth since their last battle. Even when losing, Wald's deep inner strength allows him to push on. The battle concludes with a duel against Wazy, who now uses his Stigma, and results a loss for Wald. He wishes the group good luck before losing his consciousness. Wald realised he was a mere test subject for Mariabell, but did not particularly hate her.
Afterwards, Wald is brought to Arteria with Wazy and Abbas for medical treatment for Gnosis after-effects. When they return to Crossbell around its liberation, Wald has joined the Gralsritter in a yet unknown rank.