Ren

A bounty hunter who was once allied with Ein.

When Ein joined Bat and Lin's Hokuto Army, he entrusted Asuka to him. However, Ren was secretly on the Imperial Army's side and held Asuka hostage at knife-point when Ein confronted Beron. However, Kenshiro appeared and took the knife Ren was holding and drove it through his head instead.
In the anime, Ren leads a group of bounty hunters to kidnap Asuka from her home, under orders from Beron.

(Source: Hokuto Wiki)