Nie Xu (Fc name Zhang Zhehan)
Actor
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25 years old
Staff
NIE Pack
Pureblood
Alpha

Staff
Teacher in combat

Nie Xu was originally from Wen Pack, however as a teenager, he witness how the Wen Pack people was bullying one of his friend, using poison. At that time, he was a student and knows Nie Pack leader, Nie Mingjue. He told Nie Pack leader and Nie pack leader was able to came out with a plot to rescue the child with him. Wen Rouhan knew that it was Nie Xu (formerly his name was Wen Zi Shu) and wanted to punish him. He managed to catch him and tortured him by inserting 7 big poisonous nails into the body, causing a huge immense pain. Nie Pack Leader rescued Wen Zi Shu and gave him a new, Nie Xu and a new disguise, so that Wen Rouhan will never recognized him. 

I choose the Nie Pack because of him using sword and how he is told to not be involved in another person's drama unless necessary. Under the training of Nie Mingjue, he managed to get healing as one of the skills, helping himself to lessen the pain from his nails, mediating once a month. He is also hiding the skills he learnt when he was in Wen Pack, so that he could keep his original identity hidden.