Rais is an inhabitant of the town of Ruan.
He's one of the leaders of the Raven gang who hangs out in the warehouse district near the city docks and occasionally causes trouble there. He and his fellow Raven head honchos run into Estelle, Joshua and Kloe who are exploring the city's southern district. Attracted to Estelle and Kloe, Rais and his buddies start hitting on them, with Estelle's angry response even encouraging Rais, and start threatening Joshua. Unfazed by Estelle's protests and Joshua's warning, the Ravens threaten to start a fight, but the situation is deescalated when Mayor Dalmore and Steward Gilbert arrive, threaten to call the bracers on them and Estelle and Joshua reveal that they are bracers themselves. Reminded by Deen that the three of them picked a fight with a lone female bracer before and got soundly beaten despite the advantage in numbers, the three of them decide not to press their luck and leave.
When Clem comes storming into the gang's warehouse the next day and starts shouting at the Ravens, the gang threatens to beat him up, but they're interrupted by the timely arrival of Estelle, Joshua and Kloe. This time, Rais and the others engage the bracers in battle, although in the end they're soundly beaten. The standoff continues, even after the battle, until Agate turns up, sucker-punches Rais in the stomach just to make the others pay attention and reasserts his authority over the terrified Ravens by beating up Rocco.
After or during the school festival, the mayor's steward Gilbert apparantly visits their hideout, but Rais can't remember what happened next. He and the other Ravens are controlled and Rais and two others are made to guard the second floor of the lighthouse where they're defeated once more by Estelle, Joshua, Kloe and Agate, although they put up a much tougher fight than before. After being beaten yet again, they're locked in Manoria's windmill shed until the army arrives. Since it's decided that they were being controlled, they aren't taken to Leiston Fortress and return to Ruan instead.
After Estelle and Joshua travel to Zeiss, Rais and the rest of the Ravens engage in some training and eventually enroll in the martial arts competition taking place in Grancel. Rais, Deen, Rocco and one of their buddies even manage make it to the first round of the finals where they're pitted against Estelle, Joshua, Zane and Olivier. Eager to exchange some trash-talk before the match, Rais and his buddies head over to the other waiting room to confront their opponents, but Estelle's unexpectedly high-spirited attitude flusters them to such a degree that they end up quietly walking away.
Their winning streak from the prelims doesn't hold up though and they end up losing to Estelle's team. As a sign of good sportsmanship, however, Rais, Deen and Rocco give Estelle the key to one of the sewer areas beneath the city, which they acquired by chance, so she and the rest of her team can train for the matches ahead. Afterwards, they presumably return to Ruan without sticking around until the end of the competition.
According to his combat information blurb, Rais is rather mild-natured, though he's still a bit of a ruffian. Of the three Raven leaders, his personality lies a bit in the middle; not as hot-tempered as Rocco, but still less level-headed than Deen. By his own admission, Rais is attracted to tough women and is even encouraged in his advances by Estelle's forceful rebukes. Unfortunately for Rais, tough women generally don't like him back. According to the rest of the gang, Rais was so foolish as to pick a fight with Lieutenant Julia Schwarz while she was in Ruan to handle Mayor Dalmore's arrest and got beaten so quickly he barely even realized what happened. Seeing that he had already been defeated in combat by Estelle and Kloe as well as Carna in the past, it's not unlikely that Rais has never met a tough woman he wasn't outmatched by.