She displays brutality against Fatui's new recruits and uses deadly force against them, despite the clear difference in power. He seems to have immense pride and arrogance regarding his skills in combat and fighting,

arrogant and ruthless

She always comes off as having a lewd streak, being extremely flirtatious and lustful with Alto Goldfield, her summoner, and even says she feels ecstatic whenever she tastes/feels his golden mana.Vermeil is a tall, curvaceous woman with shoulder-length violet hair, deep vermilion eyes, horns, a spade-shaped tail, small fangs and pointy ears. 

being extremely flirtatious and lustful with Alto 

Xueli used to be a typical cute girl, but she changed drastically after she was humiliated by her ex-boyfriend, Du Yuze. She is very smart. Naturally talented, she was always ranked second in school scores just below Haoyi, who was a genius. She gets jealous and angry if she sees Haoyi with other girls going as far as trying to kill them if they come near him believing in their own world that Haoyi is her husband. He will even threaten Haoyi if necessary. Xueli also has a brave side in his willi

She's a Yandere but she doesn't get to kill someon

Babel has a domineering personality and is obsessed with holding power, but maintains enough control over her outward expressions to maintain a cordial and professional front. She is a master at manipulation