Yuri Briar (ユーリ・ブライア, Yūri Buraia?) is Yor Forger's younger brother and a twenty-year-old man who works in the State Security Service. He keeps his job at the SSS a secret from his sister, instead pretending to be a normal civil servant at the foreign ministry.
Yuri is a young man in his twenties. He has a very small cowlick on top of his straight black hair with uneven bangs. He also has red eyes. When at work, Yuri wears the SSS's standard uniform. When leaving work, he wears a coat over his black suit and tie, along with black gloves.
Yuri has a sister-complex, and even at an early age, he would be doing everything he could to get Yor to praise him with affection. Though this could be due to his mother dying at a very early stage in his life causing him to get very attached to Yor as a mother figure.
When on the job, Yuri is shown to have a very appealing demeanor, calmly extracting information from the people he interrogates. He's been shown to be very patriotic as, when discussing "Twilight", he swiftly drops his calm air and becomes colder and angry, losing his patience very easily. He also appears to value his family, as he almost immediately resorts to violence when he learns of the personal excuse for his affair.
During his childhood he lived in Eastern Nielsberg, both of his parents passed away when he was young, leaving both him and his older sister, Yor, as orphans and causing them to be poor and unable to afford books or school supplies. Around this time Yuri began developing his sister complex tendencies when he began doing everything he could to make Yor happy and to shower him with her affections, eventually leading him to work as a diplomat at the foreign ministry until about a year ago, where he began working for the SSS.
Yuri calls Yor, asking when she is going to get married. He explains that he may be promoted at work, which would make him too busy to look out for her, which makes him worried. He brings up introducing her to someone, but Yor lies that she already has a boyfriend and says that he will ask Dominic for a full report on him. At the end of the call, Yuri says that he will be the one to drive out her boyfriend if it turns out he is a bad person, and leaves the call after excitedly saying he cannot wait to hear about him.
Since Yuri is protective of his sister, he acts rudely towards Loid for thinking he is unworthy of his sister.
Because of Yor raising him during his childhood, he has developed a sister-complex and will do anything to keep his sister safe, to the point of suspecting her husband of being an enemy.
Having been a very studious person growing up for the sake of his sister, he has become far more intelligent than her.
Yuri is extremely smart, able to work as a diplomat at a very early age. Despite this, however, his intel is that of amateur when he's compared to Loid, as he follows what was in the Ostanian Intelligence manual word for word during his dinner with Yor and Loid, which allows the latter to quickly figure out that he was picked up by the SSS.
Yuri is said to be very talented for his age, allowing his boss to let Yuri tag in for a senior officer for interrogation.
Yuri very durable, most likely due to his sister inadvertently hurting him in his youth. As an adult, he is durable enough to take two of Yor's drunken hits albeit sustaining heavy amounts of injuries enough for people to tell him to go to the hospital.