Karin is an automotive company in Grand Theft Auto IV and Grand Theft Auto V based on Toyota. However, the Sultan RS and Korean Mob Sultan, are modified like Subarus even though they are both based on a Lexus (Toyota's luxury brand) combined with a Mitsubishi; and the Intruder is based on Infinitis.
The name might be a parody of Kia as they spelled similarly and are girls' names; the logo also bears resemblance to their corporate logo (mainly the top left tip of the 'K').