The SS Mishen is a Ge-L3-1A - Vampire-Class Patrol Craft, recovered during the salvage operation to obtain the Kozan Class Heavy Mining Ship that belonged to Takeyu Nayacesen. The ship is owned by Takeyu, but it's currently in the possession of his company, Nayacesen Industrials.
The Ship currently serves as escort duty for the SS Kozan Maru Shime, it is, however, already going to be replaced at a later date with something more up-to-date..